Unexpected deallocation of the audio resampler

[caffeinism]

The AudioCodecContext contains a Resampler. This Resampler consists of Graph, and there is a mutual reference relationship between the Graph and the FilterContext. At some point during execution, the Graph is unexpectedly freed, causing the program to crash.

When:

container.mux(audio_stream.encode()) # flush remain packets

Below is the error message:

  File "av/audio/stream.pyx", line 17, in av.audio.stream.AudioStream.encode
  File "av/audio/stream.pyx", line 26, in av.audio.stream.AudioStream.encode
  File "av/codec/context.pyx", line 398, in av.codec.context.CodecContext.encode
  File "av/codec/context.pyx", line 385, in av.codec.context.CodecContext._prepare_and_time_rebase_frames_for_encode
  File "av/audio/codeccontext.pyx", line 28, in av.audio.codeccontext.AudioCodecContext._prepare_frames_for_encode
  File "av/audio/resampler.pyx", line 111, in av.audio.resampler.AudioResampler.resample
  File "av/filter/graph.pyx", line 215, in av.filter.graph.Graph.pull
  File "av/filter/context.pyx", line 126, in av.filter.context.FilterContext.pull
  File "av/filter/context.pyx", line 83, in av.filter.context.FilterContext.graph.__get__
RuntimeError: graph is unallocated

[WyattBlue]

1. Can you confirm that you're on the latest version?
2. What code triggers this exception?

[caffeinism]

1. yes I am using the latest version.
2. it's container.mux(audio_stream.encode()), which I called to process the preceding audio stream and then flush it. This doesn't always happen, and it happened randomly after processing multiple requests, so it's hard to reproduce, but it happens consistently.