Stereo for 32x/sega cd/genny combo

right now i have a 32x/sega cd/genny combo all model 1's. currently the output i use is the cruddy video/mono cord that came with the 32x (white and yellow plug is all, no red). i've put right and left audio plugs in my sega cd to get stereo sound but some of it is missing (especially noticeable in the bios for the sega cd). so my question is, if i get the "stereo av" cable for the 32x from it would output stereo sound for all 3 systems right?
no. the model 1 only outputs mono through the AV jack to the 32x.

you could get the audio mixing cable (stereo headphone plug on both sides) and connect it to the genesis' headphone jack and the "mixing" jack on the back of the segacd, then use the segacd's audio-out jacks (2x RCA).