Hi Mark,
Its possible that CD will seemingly play OK but not rip OK.
The underlying algorithms differ including how they attempt to error correct.
If its an option for you I would try ripping the troublesome CDs on a computer and then uploading the ripped tracks to your B2.
Other ripping software can allow you more control of the rip process including the speed at which it attempts to rip. Slower rip speeds can often times get over errors more successfully
John