In dbPoweramp I'm making sure that Album Artist is populated with a single artist. What's happening in JRiver is that numerous albums are showing up multiple times, each with a different artist for different songs. When I look at the tags, Album Artist (auto) is populated with that artist and the Album Artist tag is empty. That is NOT the way I ripped the CD, I'm positive each Album Artist tag was filled.
You've got something going on that's not related to MC's use of Album Artist (auto). MC won't just randomly fill or clear data fields on files you import. It won't clear Album Artist unless you tell it to. For one of these albums you are talking about, how does MC import it? After you ripped it in DBPoweramp of course? Is there any other software involved?
I would encourage you to try some experiments. Take one of the offending files and do a "tag dump" on it, so you can see what tags are INSIDE the file:
Highlight the file. Edit > Tag to open the tagging window. At the top of that Tagging Window it will show something like: MP3 - 3:35 - 23 MB . Click that text! This will bring up the hidden tag dump window and let you see the raw tags. See if you can see any values for Album Artist. Maybe DBPoweramp is writing you Album Artist to a different tag or something?
If you *do* see Album Artist in there, you can force MC to update by re-reading the tags from the file. Library Tools > update Library (from tags) .
You might also try a fresh rip with DBPoweramp and do these above steps before anything else to get an idea of what's going on.
Good luck. Post back here with your results and we can try to help you further.
Brian.