Marzen

I recently attached my stereo to the Monitor Out jacks on the rear of my HT 3061A tv. The problem is, I don't get any audio out from here when I select a component video input (the tv's speakers still work though). All of the SVID and composite inputs carry through just fine. On a semi-related note: I noticed that my Aquos LCD tv at work will mute the audio if I remove the component video input cable even though the L&R audio cable is still attached. Is this part of the protocol for component video, or is this just part and parcel for 'out of band' engineering?