This is because according to a thread on Reddit, users have discovered that the latest HomePod beta software is causing their smart speakers to overheat. According to the post, “I advise to unplug anyone of your HomePods that are hot on top leading to your logic board failing or have the issue on audio os 15 where Siri can’t pause music when it is playing music, touching the top will only skip it.”
It also seems that if your HomePod gets damaged as a result of you installing the beta software and even if your HomePod is still under warranty, Apple will not cover it. Like we said, this is undoubtedly a problem but it’s good that such an issue was discovered during the beta versus the final release.
It is unclear what could be causing the problem and cause the HomePod to overheat, and to make it worse, apparently once you install the beta there is no way (or no easy way) to revert back to the original. So if you were thinking of taking part in the latest beta, you might want to consider that.