Homepod 2 sound issues after 18.1 software update

After the recent update of HomePod 2 to software version 18.1, it began to hiss in inactive mode. When you are next to it in a completely quiet room, you begin to hear a pressing hiss coming from the bottom of the device. Rebooting helps (temporarily). After a few hours (sometimes it's 2-3 hours, sometimes every other day), the HomePod 2 starts hissing again (not loudly, but enough to hear). Resetting to factory settings did not help. Who else has encountered this?