Here are some examples of how to do commands without using XML. In the examples below, it is assumed that the address of your player on the network is "http://empeg", substitute the correct address for this as needed.
To access the built-in HTML playlists of Hijack (no XML), the command is:
http://empeg/?fid=101&ext=.html
From there, you can stream, download, or play any tune or playlist on the player.
Play
http://empeg/?serial=%20&nodata
Pause
http://empeg/?serial=W&nodata
Fast Forward
http://empeg/?button=Right.L&nodata
Rewind
http://empeg/?button=Left.L&nodata
Next Track
http://empeg/?button=NextTrack&nodata
Previous Track
http://empeg/?button=PrevTrack&nodata
Volume Up
http://empeg/?button=VolUp.L&nodata
Volume Down
http://empeg/?button=VolDown.L&nodata
Info Mode
http://empeg/?button=Info&nodata
Next Visual
http://empeg/?button=Visual&nodata
Toggle Shuffle
http://empeg/?button=Shuffle&nodata
Sleep
http://empeg/?button=Top.L&nodata
I haven't tried all of these out, I was just pulling code from CharcoalGray99's page. No warranty on the above items, expressed or implied.