Sound only on one side of the car
I installed the Joying B08J3VNMBX  in my Mercedes GL450 and had it on radio while testing the install. All is fine on radio; all speakers work just fine, DSP works perfectly. I also installed two separate amplifiers to be able to take full advantage of the DSP system; one is for the surround and one is for the sub-woofer. Again; everything is perfectly done and the radio sounds excellent on all speakers. All other sources only play out of FR and RR + sub. I changed the wires from one speaker to another to make sure that it's not a speaker/wiring problem and it is NOT. This unit only puts-out sound on all speakers in FM radio mode.Please help. I'm still under the replacement/return period. Also, I totally love the unit and this is my second one; the other one works with no issue.
I fixed the problem myself... Yoying support is really very bad! There is a hidden setting (very well hidden). It’s under the greyed-out mono setting. It’s a system balance and it was all the way to the right side. Hopefully it’s going to give me joy from now-on. I have two of them and the other one was fine out of the box.
Hi Adrian, I am having the same issue only it is with the fader setting. I get no sound from the rears when fading to the back. I looked for the well hidden mono setting and I can't find it anywhere. I have the JY-VQ131N4GN Android 10 with Jan 2021 firmware.

Can you tell me where this setting is located?