Support more than 2 channel and 48k sampling rate

[RomanJos]

Hi, I tried investigating an issue me and my friends had for a long time using Telegram, whenever we tried to screen share with sound, no audio could be heard.
I discovered the hidden mode and used debugmode to get insight at what was happening, I stumbled across this part which indicate an error at initializing an audio component preceded by a sampling rate which is not mine :

2021-9-23 17:38:36:761 (bitrate_prober.cc:114): Probe cluster (bitrate:min bytes:min packets): (1052000:1973:5)
2021-9-23 17:38:36:761 (bitrate_prober.cc:114): Probe cluster (bitrate:min bytes:min packets): (1052000:1973:5)
2021-9-23 17:38:36:775 (webrtc_loopback_adm_win.cpp:739): Loopback ADM: Failed to initialize IAudioClient.
2021-9-23 17:38:36:775 (audio_device_buffer.cc:180): SetRecordingSampleRate(48000)
2021-9-23 17:38:36:775 (audio_device_buffer.cc:200): SetRecordingChannels(2)
2021-9-23 17:38:36:775 (bitrate_allocator.cc:523): UpdateAllocationLimits : total_requested_min_bitrate: 35733 bps, total_requested_padding_bitrate: 0 bps, total_requested_max_bitrate: 35733 bps
    2021-9-23 17:38:36:784 (webrtc_loopback_adm_win.cpp:739): Loopback ADM: Failed to initialize IAudioClient.
    2021-9-23 17:38:36:784 (webrtc_loopback_adm_win.cpp:739): Loopback ADM: IAudioClient for loopback could not Start.
2021-9-23 17:38:36:784 (channel.cc:902): Changing voice state, recv=0 send=1 for {mid: 0, media_type: audio}

I researched those errors on google which got me here. I tried it and it worked ! Setting anything else result in no audio at all.

Thats all, I just want to point out that on my hdmi output, having 2 channels and 48k still don't work though.

Tell me if it is something you already implemented (1ea86a3 ?). In that case I'll have to search again. Thanks !