Description of Problem:
When reading tracks, if a CD that is not recognised by the cddb is
inserted _after_ tracks are read from a CD that is, the non-cddb CD's
tracks get misnamed.
It happened once; I haven't tried it again yet.
Steps to Reproduce:
1. Insert CD that is recognised by the CDDB and read tracks from it.
2. Replace CD with one that is not recognised by the CDDB
3. Select the CD device again in order to get xcdroast to re-read the
table of contents
Tracks have the names of those from the previous CD.
The user is required to hit the 'Query CDDB' button after a CD change.
xcdroast does not check if a new audio Cd has been inserted.