Error opening sound device

I can record ok with audacity recording bits from old cassette tapes

but now I find I get to the end and want to play back to listen to the quality

I hit play and a window comes up …

error opening sound device
try changing the audio host playback device and the project sample rate …

luckily I find I can save the recording in mp3 ok but it would be nice
to be able to playback the recording on audacity just to clean up one or two things

Just uploaded a 3 min mus file to audacity and find same thing happens … cant play that either