Thanks, Mark. I think as a workaround I will just insert a delay after x number of serial commands to allow the player to "catch up". I can see when I insert a lot of songs the playlist size slowly increments over a matter of 5 or so seconds to match the amount of songs actually inserted. It should not be a problem for someone who is inserting/enqueueing 50+ songs to have to wait an additional 5-10 seconds for the entire playlist to be up on the player. The first track will be sent immediately, so no wait there.

Unless this is something that can be fixed in the player software for a later release.