Found (and solved) the problem. Insufficient disk space!! Not flagged by Wavepad, but something to be aware of. If you read this Gato, this may be same for u.
I am a happy camper again -- with Wavepad -- and I'll accept responsibility for this 'problem'. Still, if Wavepad could flag it when disk space is getting tight.......that would be a welcome preventative measure.
Regards