I'm a
very
recent user of an Apple Silicon (M1) MacBook Pro which I got as a gift from a friend. Fortunately, Linden Lab was so kind as to provide the SL Viewer with a Universal Binary version.
Unfortunately, the
SLVoice
plugin that enables Vivox voice communications is compiled as an Intel-only application. Simply put, unless you happen to be in a WebRTC Voice simulator server, voice
will not work
.
Currently, I don't have Rosetta 2 installed (and don't intend to!), so, perhaps unlike the majority of Mac users with computers bought since ~2020 — who had no choice but to use Rosetta 2 to run the SL Viewer.
As such, once they installed the Universal Binary, even though the 'main' code was now being running directly, the SLVoice plugin was using the Intel emulator from Rosetta 2. People (as well as your own team!) just hadn't experienced any issue, so the SLPlugin's functionality was never checked for compatibility issues.
Note that currently Apple Silicon users have only two options, if they wish to continue to use voice services in SL:
  1. Install Rosetta 2.
  2. As an Estate Owner, file a ticket to request a move of the region servers to the so-called "Second Life Preflight" version of the simulator server, which supports WebRTC Voice.