Do you have large playlists? How many threads do you use?
Try cleaning up temporary files in Windows, maybe this will improve the situation, but I doubt it. Also try limiting the number of conversion threads to one and see if this fixes the problem.
Yes, to be frank I only have one playlist with all my music in it... 3082 items. I use 3 threads, that's the maximum the plugin will let me.
Will try to clean the temp folder and limit the threads to 1 and see what I get.