Hi Kirk welcome to the forum.
In most cases either will work but just to be safe get the mono plug. I use both but in the past I do remeber a person on the forum who had issues with trying to use a stereo plug.
What are you setting up?
My system is:
H/K
AVR 7200
DVD 25
DVD 50
CDR 26
Panasonic DMR E80-H recorder
Comcast Hi-Def DVR
APC 1400RM Smart UPS
Toshiba 42HP95 Plasma
Infinity Alpha 50's
Alpha Center
Alpha 10's for the rear.
My issue was the components near the bottem of the rack are blocked by the coffee table from the main seating position.
My thought was to use the IR receiver on the TV to feed the rest of the components.
Another question on this is if one component is off does it still pass the signal to the next one in the chain?
Let me know what you all have done.
Thanks for the fast responces,
Kirk