From here always we advise against Install beta software released by Apple for your devices. That is work for the developers to test, on devices that they have for that, to test and detect the bugs that these betas may present.
But there are always adventurous users who want to be the first to try the news of these betas, before they are official for everyone. If you are one of those "impatients" who is testing the beta software version 15 for the HomePodsBe careful because your speaker can overheat. And Siri is not going to warn you that she has a fever.
Even though beta versions of the HomePod and HomePod mini software are only technically available to guest users, the device profile required to install the beta software can be easily found via a quick Google search. This means that people who are not invited to the testing program Appleseed they can still install the beta firmware for the HomePod.
So if you are one of those adventurers who are always willing to try Apple betas before they are official versions, be careful if you have installed the beta version 15 of the software to your HomePod, since it is giving some problem, more or less important.
Various user complaints on Reddit
On the popular platform Reddit, there is an open thread about such errors. Here Several users explain that they advise unplugging any of their HomePods that are hot on the top, as it can cause motherboard failures.
One of the most common complaints in such an open thread is that the HomePod gets abnormally hot when running beta 15, and in some cases the HomePod even shuts down completely, apparently due to the overheating.
The problem is serious, since in the HomePod there is no way to be able to restore older software to installed. We have to wait for Apple to launch a new beta to correct the error. So if this is your case, unplug it, and wait.