Probably nothing. The Beta versions play error tones for "non-critical" errors. I've never used a beta where I don't get error tones on many occasions when, from a functional perspective, nothing is going wrong.
If you look at the detailed logs for most software there are rafts of non-critical errors. And NVDA release candidates and released versions do not report these via those tones while the testing versions do.
Brian - Windows 10, 64-Bit, Version 21H1, Build 19043
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