Voltage stabilizer with servo motors?
Assuming the stabilizer is not broken, It makes strange sounds if:
1. The voltage is going nuts, the stabilizer tries to stabilize it and the servo motor will make sounds. <-- normal
2. The stabilizer is operating near max or at max from it's max power rating (capacity). <-- not normal, you pick the wrong capacity
From your explanation, nr. 2 seems to be happening but it could also simply a coincidence that while you are playing, nr. 1 happens. I can not tell for sure.
Personally, I would not use traditional stabilizer anymore and would rather use a good UPS.