inpulse 500 - no sound from right output

everything about the unit works fine except for the fact i get no master output of any kind from the right deck. i can monitor the signal in the headphones for that channel; i get levels showing in the meters, but i get no sound on the right channel, whether im monitoring through the master headphone, master output or internal software output.

everything else works fine (buttons, jogs etc and the left channel works perfectly.

ive looked all over the net for solutions or schematics but to no avail. hoping to get some help here. thanks.