Yamaha motif xs8 no sound from any of the outputs

by taylor
(caribbean)

my motifs recently stop producing sound out of all the out puts everything else works perfectly but there is no sound no voice demo anything going out i can hear electric buzz when plugging in my headphones so i know there is electric signal getting to the outs i have tried everything resetting factory reset and nothing. i did unhook all processing boards and stuff inside the keyboard hooked it up and then it worked for a short while and then went back to doing the same thing but ting to replicate this did nothing a second or third time

any ideas or suggestions auto what to do