Planetary mixer and mixing speed - help needed

Good day fellow bakers!

I've recently purchased a planetary mixer for my home micro bakery. Until recently, I used to mix all by hand, but the quantity is just too much for me to go on and continue growing.

I have a difficulty in mixing the dough properly. I live in a hot country (the Philippines), and even though I add ice water to the dough mass, I think that the planetary mixer is over heating the dough and hence breaking the gluten, as the same recipe yields different results with liquid dough for the mixer.

The slowest speed works on 105 RPM, which is a little too fast than desired for the first gear setting. At this stage I think that I have two options:

1. buy a variac and slow the mixer.

2. get into fast mixing techniques. I've heard about mixing techniques utilizing high speed mixing speed for a shorter period of time, or in intervals. But I can't find information about it online. Does anyone have experience with high speed mixing?

Looking forward for some expert advice!

Cheers, Dan