Music on Hold via Line-In buffer issues

Asterisk 11.12.0 (CentOS) with a SiriusXM radio plugged into line-in. Computer is an HP desktop. I have everything working great, though it seems like when you first dial-in and listen to music on hold, you get 2-3 seconds of whatever was left in the buffer and then it switches to real-time music. Dial-in, hear a song. Dial-in 10min later, and I hear 2 seconds of that same song, then it changes to a new song (currently playing) and will play forever (well at least 20-30min while i listen). I have tried all sorts of options in the ast-playlinein script dealing with shorter/longer buffer time, buffer size, period time, period size, etc with no change. have not figured out a way to have no buffer, it always does the same thing. any ideas? I am just guessing on the cause here.

/usr/bin/arecord -q --buffer-size=2048 -f S16_LE

Thanks for any ideas/help.