Hi,
I suspect that the old MP3s sampling rate is a non-standard rate ie. not 44,100 Hz. I suggest trying changing the Tools - Options - Audio - DSP & Output Format settings to enable output format and change the output format to the number of channels/speakers used by your pc then click Done. On the Audio Options screen, I'd then confirm that the "Resample uncommon sample rates automatically (required Output Format to be enabled)" is checked. Once you do this, try playing one again. If this works, all good; if not, more diagnostics could be required.
In any case, if I were you and you still have the album, I'd rerip it to FLAC or another lossless format for future use.
