I've had a crack at fixing this old bug -
http://www.rockbox.org/tracker/6411 - when you delete or add a track to
a playlist, resume starts the wrong track afterwards. Happened to me all
the time when copying new podcasts across.
Given that there isn't much space to keep the settings in, I store the
crc32 of the file name, then restore the stored index only when the name
hasn't
changed. Otherwise the resume code goes looking through the playlist for
a matching crc. This is obviously open to collisions, but it seems "good
enough" and has worked so far for me. Slowdown might be a problem, but I
tried with a 900 track playlist and it was barely noticeable.
http://gerrit.rockbox.org/372
