Google’s Pixel smartphones may be considered the best Android devices available right now, but they’re certainly not without their issues. One of the handsets’ reported problems involves audio distortion when the volume is at its highest level. This was initially thought to be a software problem, but a Google Support specialist says it’s related to the hardware – which is much more serious.

Last month, Redditor Mark “badmark” Buckman posted a video (above) of his Pixel and Pixel XL exhibiting a popping, distorted audio when using a piano app with the handsets’ volume cranked all the way up. Other users reported experiencing the same problem with music and videos played at maximum sound levels, and some sites were able to replicate the effect.

The problem was thought to be software-related; Google even said it would release a patch to address the issue. In the meantime, Buckman posted a “fix” using a third party ROM, which you can see here.

However, an email conversation between a customer and a member of the Google Store Support team reveals that the audio distortion is a known hardware fault present in “a select build of device,” though they didn’t go into specifics. It seems the fix merely restricted the speakers from reaching their maximum volume, thereby stopping the distortion from occurring.

The message also states that Google is not currently offering refunds for the issue but it is covered by the warranty service, which means replacing the affected handsets with new ones that, hopefully, don’t suffer from the same sound problems. But without Google releasing more details, there’s no guarantee that the replacements won’t also have audio distortion.

Other reported Pixel problems include purple shade and random artifacts affecting the cameras, LTE connectivity problems, battery life issues on some models, and numerous reports of the phones suddenly freezing and becoming unusable.