Are you sometimes stuck with a buffering video or a slow-loading Web page, and wonder why your high-speed internet has slowed to a crawl?

Have you ever contacted your internet provider about the problem only to hear that it's you, not them?

You're not alone.

The Republic this summer surveyed hundreds of Arizonans about the performance of their internet service using a standard internet-speed test. Dozens reported their service was at least 25 percent slower than what they're paying for, even when their computers were plugged directly into a modem or router. Hundreds more reported slow speeds with their Wi-Fi connection.

The test results, from internet users all over the state, highlight the wide variation in service, and that internet providers sometimes fail to match their advertised speeds.

Internet service providers often point to factors beyond their control — the customers' equipment, their location and overall demand for bandwidth — to explain slow service.

But pinpointing the cause can be difficult.

Scrutiny of internet service is done almost entirely in response to customer complaints.

The federal government, which since 2011 had produced an annual report on the performance of broadband service nationwide, hasn't released the report in nearly two years. This has happened as companies have marketed dramatically faster service with names like "gigablast" with few, if any, guarantees on actual performance and their customers rely more on fast internet connections for streaming entertainment content and smart devices.

"The contract says, 'We're going to do our best effort,'" said Nicholas Economides, an economist at New York University who studies the telecommunication industry. "And you can't really tell them, 'Oh, you didn't do your best effort.' You have no idea if they did their best effort or not. Unfortunately the contract does not guarantee the speed, and therefore, you can't hold them to that."

The Republic received 740 responses from Arizonans to a June survey. It asked readers to run a test from Speedtest.net — the same service Cox and CenturyLink ask customers to use — and then report the results with information about how and where the test was taken.

Because the responses didn't represent a random sample of Arizona internet users, The Republic attempted no statistical analysis of the data.

Making their best effort

But for Arizonans living online, periodic frustration with internet service appears to be a nearly universal experience — even for the technologically savvy.

George Landrum, a 30-year-old IT professional who lives in Scottsdale, reported download speeds of 502 megabits per second on a hard-wired connection, just over half the speed promised by his gigabit plan from CenturyLink Inc. That's not uncommon for him, he said.

Landrum said in an interview that his setup and equipment aren't the issue, but he's not surprised it's slower than the service the company promised.

"I've done everything that I can on my end to make my internet as fast as possible," he said. "For something that's consumer grade, my experience in technology has always been ... it's going to be good enough, not perfect.

"I'd like to see them advertise it more as a 500-megabit service, but it's hard to stay competitive in the marketplace if you're not willing to lie in your advertisements."

Landrum said the variation in speed doesn't have much of a practical effect on his life, but he is concerned internet users with cheaper plans could experience more-tangible impacts.

"At this level of service does it really matter? Not really," he said. "What really irks me is if I'm on 150 mbps with Cox or 40 mbps with CenturyLink, that's a serious problem if they're only giving you half of what you paid for there because that becomes a bottleneck and consumers really feel that pain."

Tom Klabunde, a 66-year-old retiree from Tempe, said he has noticed for years that his service from Cox Communications has fluctuated significantly without any explanation.

"There's a lot of times that the speeds just aren't even probably the number that you saw," said Klabunde, who reported download speeds of 27.9 mbps compared with his 50 mbps plan from Cox. "I don't know why that is."

Arizona's largest internet service providers, Cox and CenturyLink, declined to be interviewed and instead provided written statements.

“Our network has consistently performed at or above advertised speeds, and we provide customers with tools to measure their speed and data usage," said Cox's vice president of public affairs, Susan Anable. "Cox is committed to providing the best possible service for our customers but do not guarantee speeds in our advertising or service agreements due to a number of external factors that can impact speeds in the home.”

CenturyLink spokeswoman Courtney Morton said: "The actual speed customers experience will vary depending on not only the bandwidth provided to the customer by CenturyLink, but also other factors outside of CenturyLink’s control such as customer location, the quality of the customer’s computer and network, and the websites accessed by the customer. We encourage our customers to contact us should they have any questions or issues."

Why is your service so slow?

The bandwidth provided by ISPs is just one factor in what actually determines your internet speed at a given moment.

Here are other factors, according to experts and the companies:

The age of your equipment—modem, router, computer.

The number of devices connected to the internet.

How you connect to the internet—Ethernet or Wi-Fi.

Congestion from multiple residencesthat share the same connection.

"This is not unique to Cox customers," Cox spokeswoman Andrea Katsenes said in an email. "I am sure you hear similar challenges from your readers who obtain their internet service from other internet service providers. That is why Cox is transparent in our messaging, stating that internet speed levels are 'up to' an offered service level."

Broadband connections are subject to different loads at different times, so consumers can experience significant variation depending on when they connect.

"There's probably a window of expectation that people should be able to have," said Marguerite Reardon, a senior writer at CNET who has reported on technology and telecommunications companies for 20 years. "If it's consistently horrible on a particular stretch of network, that's problematic."

TEST YOUR SPEED: Run The Republic/azcentral speed test and tell us the results

Many people access internet at home through Wi-Fi connections, which internet service providers and experts say can greatly diminish the speeds they experience. For example, your actual internet speed can depend on your router's placement and how far away you are from it when you connect.

Internet service providers sometimes blame customers' equipment for slow speeds.

"A lot of things that people have problems with ... is just they have poor equipment in their house," Reardon said. "That's incredibly frustrating for people, too."

To minimize this effect, Cox provides what it calls Panoramic WiFi with specific equipment and installation from technicians who study your home to identify dead zones. The service costs at least an extra $9.99 a month.

When the problem isn't your setup

But there are other reasons your internet might be slow that have nothing to do with your equipment or connection.

Internet arrives at residences much the same way as water: There are central conduits and smaller lines that branch off to each home.

If you are connected to the same line as many others in your neighborhood, the overall load from those connections can slow service for everyone.

A consumer would not typically have access to that information before they sign up for service.

Most companies, including Cox and CenturyLink, list modems designed to work best with their service. But neither company told The Republic what kind of forewarning they give about location and other factors outside the customer's control.

The variety of factors that can influence internet speeds allow providers to brush off customer complaints, said Landrum, the Scottsdale CenturyLink customer.

"It's really, really easy for ISPs to just blame the consumer — say, 'You're doing it wrong, it's your router, your computer is slow,' something like that — when in reality it's not that hard to do a speed test and see you're not getting the bandwidth," he said. "Just because there's a lot of factors that could potentially be in play, it doesn't change the fact that they're not delivering what was advertised."

Klabunde, the Cox customer from Tempe, took the test in June with a modem that was at least 5 years old. He upgraded his modem since then but has seen no improvement.

He ran another speed test during an interview with The Republic. The result: 16.9 mbps with an Ethernet connection, worse than it was with his old modem.

"It's just kind of highly variable for no discernible reason," Klabunde said.

Reardon, the writer at CNET, said for the most part fluctuations aren't noticeable to consumers, and the service most people pay for gives them access to greater potential capacity, not necessarily a consistent level of service at that speed. But if someone experiences long load times for videos or slowing of their other daily activities on the Web, they should investigate.

"If it's impeding you (being) able to do what you need to do on the internet, or you feel like you're overpaying extensively and you're not getting the service that you need, then that's when you've got to file a complaint with the FCC, go to the FTC, talk to your state attorney general, definitely report those issues," Reardon said.

Who holds providers accountable?

Oversight of ISPs, which are part of the broader $430 billion telecommunications industry, is sparse.

Consumer advocates have long decried the lack of regulation of internet service providers, which operate with little or no competition in many parts of the country.

In Maricopa County, some areas defined by Census blocks have as many as seven internet providers, while others have just one, according to 2016 data from the FCC.

"In most parts of the country, there are only one or two providers," Economides, the NYU economist, said. "That's very little competition actually, and that's one of the reasons why prices are high. If you only have two companies, and you're dissatisfied with one, you have to go to the other. You might be dissatisfied with both."

The Arizona Corporation Commission says the Federal Communications Commission has ultimate authority over the industry, but it's unclear how active the FCC is at ensuring companies deliver on their promises.

The Federal Trade Commission can also investigate cases in which ISPs are accused of deceptive marketing.

In the past, the FCC published yearly reports comparing measured speeds with advertised speeds, rarely finding any issues. Its last report was published in December 2016.

A lawsuit brought by the New York State Attorney General against Charter Communications casts doubt on how effective the FCC is at measuring internet speeds. The lawsuit alleges that Time Warner Cable, since it was purchased by Charter, deceived regulators by conducting tests during off-peak hours and promising to upgrade equipment.

"By gaming the FCC speed tests in this manner, Spectrum-TWC (Charter) concealed the fact that it failed to consistently deliver the promised speeds to its subscribers under actual network conditions," the lawsuit alleges.

The lawsuit also alleges that Charter's predecessor:

Leased outdated modems it knew could not deliver the speeds it advertised.

Claimed Wi-Fi service would be just as fast as its wired service.

Didn't address deficiencies within its network that led to overcongestion in certain areas.

Charter, which operates a network under the name Spectrum in Yuma, said in a statement that the company has made significant investments in New York.

"We are disappointed that the New York Attorney General chose to file this lawsuit regarding Time Warner Cable broadband speed advertisements that occurred prior to Charter’s merger," company spokesman Dennis Johnson said. "We will continue to invest in our business and deliver the highest quality services to our customers while we defend against these allegations involving Time Warner Cable practices."

Few measures are in place to prevent what Charter is accused of doing. Reardon said it's immensely difficult to proactively test for issues in broadband networks.

"It would be time consuming and not really cost effective to try to preemptively test every particular network to certify that it is up to snuff," she said. "It seems like if people are having a problem, it makes more sense for people to report where they are having a problem and then try to rectify that problem."

Then there's the longstanding concern about a lack of competition — even as internet access becomes increasingly central to everyday life.

Katsenes, the Cox spokeswoman, said in an email that the company's service and success speak for itself.

"At Cox, we believe our customers provide the most important oversight of our services and we know they have choices in providers," she said. "We are committed to educating our customer on how to improve their internet experiences and provide access to Cox technical support experts to help our customers get the best speeds possible."

Landrum, however, sees plenty of reason to be concerned about the lack of competition.

"Digital delivery and digital access is so important for everyone, more so than it has ever been," Landrum said. "It's becoming more and more difficult for consumers to have a voice. We've seen a lot of mergers in the past few years and there's more supposedly coming."

This story was informed by an Arizona Republic/azcentral.com survey of its readers. If you would like to participate, visit static.azcentral.com/speedtest.

Agnel Philip is an investigative reporter at The Arizona Republic/azcentral.com. Reach him at aphilip@gannett.com, on Twitter at @agnel88_philip or on Facebook.

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