only one xlr output is working (korg zero 4)

[cptobg]

hi guys! i have a big problem which is i have only one xlr working now. i never had to use it before , since i bought the mixer for mixin at home. i always use the rca "recording output" as a main output. today i finally take the time to open the mixer and nothing seems to be unsolder or something like that... right after that i remember that i did the firmware update. and now im asking if this can be related to the lost of the right xlr. the guy i bought the mixer told me that he never take the mixer out to a club or party. (the zero 4 is f*ck*ng clean i swear!)

So is anyone have an issue for this or know something about this that can help me?

you can reply directly to my email cptobg@hotmail.com

thanks yall