These are media files and images which were sucessfully associated with each other, up until yesterday, for some years. Ever since I ran King's Cover Art Grabber in the early days of V8 in fact.
I can't see any pattern rhyme or reason to it.
For example all of the album Black , Brown and Beige - Duke Ellington has the image
M:\Music\Cover Art\Black, Black, Brown and Beige - Duke Ellington.jpg
associated with it.
Using Quick Find has corrected, seemingly at random, 8 tracks to use
M:\Media\Cover Art\Black, Brown and Beige - Duke Ellington.jpg
leaving the other 12 tracks with the old association.
Trying a few different things I have now found that using "Get from Internet" using "Download if Missing" will tidy up some of the remaining - again a pattern between why it does some and not others is difficult to see.
Version & System Info as follows:-
Media Center Registered 10.0.173 -- C:\Program Files\Media Jukebox\
Microsoft Windows XP 5.1 Service Pack 2 (Build 2600)
AMD Athlon 1643 MHz MMX / Memory: Total - 228 MB, Free - 86 MB
Internet Explorer: 6.0.2900.2180 / ComCtl32.dll: 5.82 (xpsp_sp2_rtm.040803-2158) / Shlwapi.dll: 6.00.2900.2573 (xpsp_sp2_gdr.041130-1729) / Shell32.dll: 6.00.2900.2578 (xpsp_sp2_gdr.041130-1729) / wnaspi32.dll: N/A
Ripping / Drive D: STAR DATA 68X max MS5.00 Mode:Normal Type:Auto Speed:Max
Digital playback: Yes / Use YADB: Yes / Get cover art: Yes / Calc replay gain: Yes / Copy volume: 32767
Eject after ripping: Yes / Play sound after ripping: No
Burning / No burners found.
Test mode: No / Eject after writing: Yes / Direct decoding: No / Write CD-Text: No
Use playback settings: No / Normalization: None