Video lagging after toggle DownTrack.Mute()

[gr8den]

Your environment.

• Version: a970af3#v1.11.0
• Client: Google Chrome 97.0.4692.99
• Environment: dev machine, MacOS
• Are you using a TURN server? No. Only Google's stun

What did you do?

1. Connect to SFU. Start publish video. Video playing on destination without lagging
2. Apply mute DownTrack.Mute(true)
3. Disable mute

What did you expect?

Video not lagging after toggle mute

What happened?

Video begin play just as I click unmute but after few seconds of playing video starts lagging (I see video with ~1-2 sec delay). Source and destination is local machine (I think it's not network problem). CPU also ok i.e not performance issue

Fixing attempts

I was trying comment this 3 lines in Mute function
https://github.com/pion/ion-sfu/blob/master/pkg/sfu/downtrack.go#L181-L183

if val {
   d.reSync.set(val)
}

With this change video not lagging after unmute. But it create new problem: after unmute video starts playing after ~1-2 seconds (delay on beginning), next it's playing fine