Opened 2 years ago
#9961 new defect
two audiotoolbox device outputs won't play together
Reported by: | sabletor | Owned by: | |
---|---|---|---|
Priority: | normal | Component: | undetermined |
Version: | unspecified | Keywords: | |
Cc: | Blocked By: | ||
Blocking: | Reproduced by developer: | no | |
Analyzed by developer: | no |
Description
Trying to play 1.mp3 through a bluetooth speaker/headphones
at the same tie as playing 2.mp3 through macbook's built-in speakers
Connect a bluetooth audio device to macOS (or some other audio output than just the built-in one i guess)
ffmpeg -f lavfi -i sine=r=44100 -f audiotoolbox -list_devices true -
showed me my bluetooth speaker output was device index 1 and built-in output (macbook speakers) were index 3
ffmpeg -i 1.mp3 -i 2.mp3 -map 0:a -f audiotoolbox 3 -map 1:a -f audiotoolbox 1
This plays 1.mp3 on the bluetooth speaker perfectly, but macbook speakers are just clicking, or playing a cruddy audio, or silent. Until 1.mp3 finishes, then the macbook speakers finish playing 2.mp3 with good quality.
running
ffmpeg -i 1.mp3 -i 2.mp3 -map 0:a -f audiotoolbox 3
and
ffmpeg -i 1.mp3 -i 2.mp3 -map 1:a -f audiotoolbox 1
one after the other in separate terminal tabs plays both at the same time as each other perfectly.
but for some reason the single command line
ffmpeg -i 1.mp3 -f audiotoolbox 3 & ffmpeg -i 2.mp3 -f audiotoolbox 1
doesn't play anything on the built-in speakers (device 3), and when they are swapped
ffmpeg -i 2.mp3 -f audiotoolbox 1 & ffmpeg -i 1.mp3 -f audiotoolbox 3
doesn't play anything on the bluetooth speaker (device 1)