Okay; I have resolved this issue for me!
I don't know if this is the same problem for everyone, but I was experiencing the similar problem where the scanning would not complete.
Looks like it is related to a corrupted file
This is what I did to resolve my music listings...
Settings > Basic Settings > Rescan Media Library > [Clear library and rescan everything] > [Rescan]
This will start a new scan - it scans in alphabetical order, so have a directory open and follow the scan closely.
I watched it for a while (about 20mins) then it stopped.
I did a search on the list of known files which were scanned before it stopped and found the file(s).
Then looked a little further down in the list of files, performed another search and didn't find them in the Logitech Media Center.
You now need to narrow down the searches between the files to find out which one(s) is/are corrupt.
You will probably find the (newish) culprit that you added to your collection.
Once found; delete the suspect file(s) and perform another full scan [Clear library and rescan everything].
That fixed it for me.
I hope it helps others.
Please reply if it does
All the best,