I've just acquired an am3 and this incessant beep is driving me crazy, at first it was just after slewing, then at the end of my session I found it was beeping constantly, yes I know there's low voltage, it's still working fine as do my other mounts but they don't complain about it.
Settings are mute in numerous areas (asiair and Stargazing app as I believe there is no longer a mount specific app), it still keeps beeping. Firmwares are up to date, you'd expect such an option to be in the AMH management section of the Stargazing app, but no.
Using mains power fixes the issue, but the option to make a racket should be a user defined option, not switched on all the time.