_wait_for_termination wait

[khonkhortisan]

Error 
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Debug info:
Anki 2.1.20 (47a1bf8b) Python 3.8.0 Qt 5.14.1 PyQt 5.14.1
Platform: Windows 10
Flags: frz=True ao=True sv=2
Add-ons, last update check: 2020-02-20 18:14:23

Caught exception:
Traceback (most recent call last):
  File "aqt\taskman.py", line 65, in _on_closures_pending
  File "aqt\taskman.py", line 53, in <lambda>
  File "aqt\sound.py", line 235, in <lambda>
  File "aqt\sound.py", line 275, in _on_done
  File "concurrent\futures\_base.py", line 432, in result
  File "concurrent\futures\_base.py", line 388, in __get_result
  File "concurrent\futures\thread.py", line 57, in run
  File "aqt\sound.py", line 235, in <lambda>
  File "aqt\sound.py", line 380, in _play
  File "aqt\sound.py", line 260, in _wait_for_termination
AttributeError: 'NoneType' object has no attribute 'wait'