Mute/Unmute with SPDIF Functionality

Is it possible to allow the mute function to clamp and unclamp the audio stream so that it actually mutes/unmutes audio output via SPDIF/HDMI passthrough? To clarify: This is not a volume issue, it's an output issue. Please advise, thank you.

mpv version and platform

• mpv 0.21.0
• Linux localhost 4.5.7-202.fc23.x86_64 # 1 SMP Tue Jun 28 18:22:51 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Reproduction steps

1. Configure SPDIF passthrough (via HDMI here).
2. Press 'm' to mute audio.

Expected behavior

Audio passthrough should suspend when muted and resume when unmuted.

Actual behavior

Audio continues to play. MUTE: YES displayed onscreen. Log shows [cplayer] No volume control available, even though it's not a volume issue, it's an output issue similar to how toggling the -no-audio option would effect output; since, for SPDIF, mute/unmute should effect whether the audio stream itself is passed through or not.

Arguably, the requested behavior already exists for SPDIF if you count cycling through available audio tracks until you reach Audio: No as the equivalent of mute and cycling back to an audio track as the equivalent of unmute. But that seems like such a kludge.

Log file

mpv_spdif_mute.txt

Start by tracing the mute action described in the issue alongside SPDIF/HDMI passthrough configuration and the log message that no volume control is available. Done means muting suspends the passthrough audio stream and unmuting resumes it, without cycling audio tracks.