Quoted from YeOldPinPlayer:Your method is treating the symptom instead of the disease. Better solution is find out why the component is heating up and failing.
Certainly. It's like increasing the value of the fuses to prevent them from burning.
And connecting a fan on the 12 volts will pull a little more on the power supply ... which will also heat a little more .
On these evolved sound boards, it is imperative to change all the chemical capacitors by new ones - the original ones are over thirty years old and are cooked!
Try then to identify the IC that are hot - Replacing the EPROM and the CPU by a CMOS version can be also a good alternative.
If the speed of the voice is drifting, it means that the clock of the SC-01 is unstable. This one being generated by the 1408 (U19) and the LM741 (U21), one must look at this level. But it is imperative that the + 12v and -12v power supply are stable, otherwise the oscillator will drift. If the capacitors have not been replaced, it's not surprising.