Backport of "playsink: Hold a reference to the soft volume element" into 1.20
requested to merge tpm/gstreamer:backport-mr-3108-into-1.20-playsink-soft-volume-refcounting into 1.20
Backport of !3108 (merged) "playsink: Hold a reference to the soft volume element".
Commits:
- e36440e7 playsink: Hold a reference to the soft volume element