DDJ SR2 // EFFECTS knobs Issues

Hi, using Serato Dj Pro with my lovely DDJ SR2 always with my power supply, 2 months ago, i had issues with 4 of them moving randomly from 0% to 100% only turning up a little. 2 of them are not working anymore and only 1 is working correctly, what i have to do, is a remaping could solve my problem ?

Regards 

Yannis Cadena