BUT i have found that if one supply is physically off then no audio is outputted at all - and that isn't good. So the question is how can i get it to work if one supply is off (no power) and when both sources are on (mixed)?
It really depends on exactly what is connected to all three connections, if they are properly designed it should work fine, there should be no need (or use) for capacitors, which will already be in all three units.
Perhaps it would help if you explained exactly what devices you have hooked up and how exactly they are connected (a diagram or schematic would be nice), and what is not working the way you expect it to work.
If it works only when the xbox is turned on then the input of the mixer uses the DC voltage from the xbox for its DC bias. Use a single coupling capacitor in series with the Wii for both channels.
no joy with adding capacitors - tried a 100pf and 270pf - connected before the resistors in the circuit diagram i posted previously, when connected no sound at all. Anyone any idea of a possible work around to this? are the capacitor values too high?
no joy with adding capacitors - tried a 100pf and 270pf - connected before the resistors in the circuit diagram i posted previously, when connected no sound at all. Anyone any idea of a possible work around to this? are the capacitor values too high?