On my machine all symptoms are exactly the same, so I consider this bug to be the same one.
In my case "amixer set Master toggle" toggles 2 channels (namely Master and PCM) but unmutes only one (Master, PCM stays muted).
"amixer set PCM toggle" behaves similarly - mutes both Master and PCM, but unmutes only PCM.
All mentioned is also true with sset and mute/unmute commands.
On my machine all symptoms are exactly the same, so I consider this bug to be the same one.
In my case "amixer set Master toggle" toggles 2 channels (namely Master and PCM) but unmutes only one (Master, PCM stays muted).
"amixer set PCM toggle" behaves similarly - mutes both Master and PCM, but unmutes only PCM.
All mentioned is also true with sset and mute/unmute commands.