I have a Crossover 27Q that had its MOSFET blow up on the LED controller PCB. I had since replaced the board and have started to experience flickering, which was the first sign the last PCB was about to go.
I purchased the 200W voltage converter you recommended and will be testing it to see if it resolves the problem. One tip for people in the US using this voltage converter, make sure you adjust the jumper on the back of the converter, because by default it is set to 240V input. I think based on that setting it will not attempt to step-up the voltage and will just pass through the American voltage, meaning your new converter is doing nothing.