Grady Memorial Hospital’s medical professionals have treated hundreds of scooter-related injuries since Birds first landed in Atlanta back in May.

That’s no surprise when thousands of the dockless, rentable two-wheelers by companies such as Bird, Lime, and Jump now line the city’s streets and walkways.

In many cases, riders are to blame for the accidents they’re involved in, as many e-scooter users rove on sidewalks and through pedestrian-crammed crosswalks, disregarding recently passed legislation that bars such behavior.

But sometimes, it appears, the scooters themselves are at fault, according to a report by Reporter Newspapers.

Lime, one of Bird’s foremost competitors, recently announced that a small fraction of its vehicles have been suffering electrical issues that make their front brakes engage without warning.

“While this issue has affected less than 0.0045 percent of all Lime rides, some riders have been injured, and, although most have been bumps and bruises, any injury is one too many,” Lime declared in a February 23 blog post.

The problem tends to occur when riders are cruising fast downhill and hit a pothole—of which Atlanta has many—or other obstruction on the road or sidewalk.

Lime would not tell the publication how many users might have been impacted in Atlanta, and company representatives did not respond to Curbed Atlanta’s request for comment.

But Lime, which recently teamed up with Uber to integrate scooter rental in the rideshare giant’s cellphone app, told the publication that it’s updating its vehicles’ software to remedy the issue.

Exactly what that update entails isn’t clear, but Lime issued a press release warning riders to cruise cautiously until the glitch is worked out.

“Use extra caution in the next few days while we issue the final firmware update, especially when riding downhill,” reads the blog post. “Always stay in full control of your scooter and don’t go full speed while riding downhill.”

These malfunctions have underscored Atlanta city councilmembers calls for stronger regulations for a transportation mode that’s taken the city by storm.

Earlier this month, Atlanta City Councilmember Dustin Hillis debuted legislation that would request scooter-related injury data reports from hospitals, urgent care facilities, and other healthcare institutions.

Drafted by Council President Felicia Moore, the resolution would ask heathcare facilities to turn over information regarding “the number of incidents within the designated timeframe, type of incident, injuries sustained, number of people involved and if the incident was a fatality” on a quarterly basis, according to a city press release.

Lime’s mishaps are not the only apparent evidence of e-scooters—and not their riders—acting up.

CBS46 recently reported on a woman who is suing Uber, which owns and operates Jump e-scooters and bikes, because she was thrown from her scooter while riding downhill.

Her brakes were out, she said.

Uber, however, maintains that the waiver riders sign when registering for the cellphone app absolves the company of any responsibility for an accident.

Lime and others also require users to opt into such agreements, meaning users seem to be on their own should problems arise.

At least the current city law requires e-scooter operators to encourage their users to equip helmets before taking off. Not that many Atlantans are obliging those rules.