I have still problems with the media index. I made sure, that there are
no extra fields in the tags, and I removed all id3v1. Now I only have
id3v2.3. But some albums, artists, genres etc. appear twice. One in the
right place, and one with "unspecified". mafw lists all ok.
Rebuilding the index (mediabox and tracker) did not help.

How can I start mafw in the background? Maybe AVRCP would be possible then.