I asked loren to add this to the FAQ a while ago, I had the same problem...

Allows access to /proc/empeg_notify on the player, which is created by the Hijack kernel. The data shown in /proc includes track name/fid/position/artist/album/etc.. the same is dumped to the serial port by notify=1. Also allows for initial sequences of button presses to be run as soon as the player starts up with "Initial=xxxxx" lines in IR_Translate. Also shows FID in Vital Signs screen. If you're trying to get serial output when docked in the sled, make sure you also have [serial]car_rate=115200 in your config.ini

Tom