In addition, when trying to export media to obtain a .mp4 file I get this error message: [..\..\Src\AudioRender\AudioRenderContextConstructur.cpp-110]. Then the program closes.
BTW, all other project sequences can be playedback OK. Only the main one has this problem!
Shot in the dark here, but I'd try turning off all effects on every clip. See how things work, then turn them back on one by one and see what happens.
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