(CNN) Six months into his presidency, Donald Trump's overall approval rating stands at its lowest point in CNN polling, while three-quarters of Americans say they can't trust most of what they hear from the White House.

Overall, 38% say they approve of Trump's handling of the presidency, according to a new CNN poll conducted by SSRS , with 56% saying they disapprove. Just one other newly-elected president has held an approval rating below 50% at this point in his presidency since modern polling began: Bill Clinton, whose approval rating stood at 44% at this point in 1993.

Enthusiasm breaks against Trump by a 2-to-1 margin. Nearly half in the new poll say they strongly disapprove of Trump's handling of the job (47%), while just a quarter say they feel strongly positive about Trump's performance (24%).

Those numbers have soured in recent months, particularly among Trump's core supporters. Among Republicans, strong approval has dropped from 73% in February to 59% now. Among whites who do not have college degrees, a core component of Trump's base, just 35% strongly approve, down 12 points since February. At the same time, strong disapproval among Democrats has held steady around 80%.

On top issues, Trump's approval ratings largely tilt negative. And perceptions of the President as someone who will bring change are fading. Just 43% say Trump can "bring the kind of change the country needs," down from 48% in April, and the share who say he "can manage the government effectively" now stands at 39%, down from 44% in April.

The poll finds widespread doubts about the veracity of information coming from the White House. Only a quarter of Americans (24%) say they trust all or most of what they hear in official communications from the White House, while more (30%) say they trust "nothing at all" that they hear from the President's office. (Even among Republicans, only about half say they can trust most of what they hear from the White House.)

Trump's acumen as a manager and ability to bring change were the brightest spots for the President in polling conducted before he took office. But cracks in Trump's base of support are evident in the results on those questions now.

Among Republicans and independents who lean Republican, the share saying Trump can manage the government effectively has dipped 10 points since April's CNN/ORC poll. Among whites without a college degree, just 50% see Trump as an effective manager. Those non-college whites are also less likely to see Trump as a change agent, 58% say so now, down from 64% in April.

Still, these tepid ratings come even as most Americans feel things in the country are going well (53% say so), a number that's held roughly steady since April.

That positive feeling hasn't boosted Trump's ratings on the issues, however. He gets a mixed 48% approve to 47% disapprove rating on national security, and Americans are also divided on his handling of the economy (47% disapprove to 45% approve). On just about every other issue tested, majorities disapprove of Trump's work, including on health care policy (62%), foreign affairs (61%), immigration (55%) and helping the middle class (54%). Nearly half (48%) disapprove of his handling of taxes while just 34% approve.

Looking back over the first 200 days of Trump's time in office, just 36% say they consider it a success, and 59% consider it a failure. Both Barack Obama and George W. Bush were viewed as successful at this stage of their presidency by most Americans (56% for Bush, 51% for Obama).

Further, 62% overall say that Trump's statements and actions since taking office have made them less confident in his ability to be president. Half of whites without college degrees share that view.

The day-to-day operations of the executive branch appear to be chipping away at confidence in Trump and his management style. Most Americans (59%) say Trump hasn't paid enough attention to the country's most important problems. About the same number say his management style and the high rate of turnover in the West Wing hurts the administration's ability to be effective (58%). Slightly more say Trump has done a poor job assembling a team of top advisers to work in the White House (62%, up from 56% saying so in April).

Personal praise for the President is scarce, just 30% say they admire the President, and 34% say they are proud to have him as president. A majority (55%) say he has lowered the stature of the office of the president. Six in 10 don't consider Trump honest and trustworthy.

Looking more deeply at Trump's tweets: About 7 in 10 agree with the President's assessment that they allow him to communicate directly with his supporters without a media filter, but fewer see other positives in his use of the social media service.

A majority (52%) say his tweets are not an effective way for him to share his views on important issues, and 72% say they do not send the right message to other world leaders.

Seven in 10 say they too often seem to be in response to TV news the President may have seen, and 71% that they are a risky way for a president to communicate. Six in 10 say they are easy to misunderstand, 63% that they too often turn out to be misleading.

Few Americans report having personally shared or responded to a tweet from Trump, just 10% say they've done that on Twitter or other social media platforms.

The CNN Poll was conducted by SSRS by telephone August 3 through 6 among a random national sample of 1,018 adults. The margin of sampling error for results among the full sample is plus or minus 3.6 percentage points, it is larger for subgroups.