16bps or 32bps WMA file problem with Nero

Further to my thread a couple of hours ago I have discovered that Accuradio download some music files at 16bps and others at 32bps. Nero ( when set to burn music/wva files) only burns the 32bps files.
However when Nero is set to burn data files it burns both 16 bps and 32bps files without any problems.
Can anyone please explain the reason for this situation and if it is possible to change files from 16bps to 32bps.
Best wishes,
Peter