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Und du meinst die Leute würden das nicht mitbekommen, wenn die Übertragung über AirPlay asynchron wäre?
Nein weil sie nicht drauf achten oder nicht achten wollen....
Long story short:
Audio latency needs to be very accurate so that multiple outputs can play in sync.
- It's always precisely 2s (down to the millisecond) with Apple devices.
- There is no way to tweak it with public APIs.
Some explanations about AirPlay's implementation:
It's possible to change the latency if you use a custom implementation, but Apple usually rejects them.
- The protocol starts with several RTSP commands. During this handshake, the source transmits rtpTime, the time at which the playback starts, which is also your latency. The typical value is 88200 = 2s x 44100 Hz.
- AirPlay devices can sync their clock with the source's with NTP to mitigate the network latency.
- During playback, the source periodically sends a SYNC packet to adjust the audio latency and make sure that all devices are still in sync.