starting with firmware version 17.0.12 the position in M3U playlist from local media servers (other playlists, too??) isn't longer persistent over a device reboot (power cycle). Tested with SoundTouch 10 & SoundTouch 20.
In other word: You are listing to an audiobook, but stop within the story. If now the Soundtouch speaker power cycles, your position within the audiobook is gone, and you're warped to the very beginning of the M3U playlist.
It would be very nice, if the previous behaviour could be restored: that means, keep the playlist position beyond power cycles.