Hi guys ! I have a problem, 4 buttons of my Challenger Ultimate keyboard are not working:
F12, PrtScn, ScrLK, Pause :/
These buttons are located close to each other and have never experienced any liquid / chemical / physical harmful influence.
What I have tried:
1. Removed the buttons and tried carefully pressing their membranes
2. Manually disassembled a keyboard and checked that two films with electrical lines and contacts - are correctly located
3. Reset all the keyboard internal profiles
Unfortunately, these steps were not enough to fix these buttons (meanwhile, all t