Edit to add: glad its sorted, Paul. Not sure which Waves plug-in you used, but as long as it didn't take time to actually resample, it probably just changed the header info.
I'm confussed how you played at 44 if the dats were 48
do you mean that you had the sample rate in wavelab etc at 44 instead of 48? I would re transfer is it was me.
That would do it, yeah - different SR setting in the recording s/w than the actual bitstream.
Really, there's no reason to go through the hassle of re-transferring. Changing the WAV header sample rate just tells the playback device at what sample rate to play the data - in this case, replacing the incorrect information (44.1k) with the proper information (48k). Changing the header info doesn't change the data in any way. Try it:
[1] Open a 44.1k file
[2] Change the header to 48k and save
[3] Open the newly saved 48k file
[4] Change the header back to 44.1k and save
[5] Compare the original 44.1k and the newly saved 44.1k file
They're identical. Re-transferring is a waste of time, IMO.