I have been extracting audio using VirtualDub and have no problems til recent. I cannot save the wav file from the avi in full processing mode. When I go to save the file I get "no audio decompressor could be found to decompress the source audio format".
The sampling rate 44100Hz and Channels 2(Stereo) look normal but in file information the compression shows "unknown (tag 6771)".

How do I correct the compression?

Thanks.