I'm using Power Overload mod and I'm building a Megabase and have just reached the limit of Medium Power Poles, so now that I've installed Transformers on every City Block, my entire base is rumbling with AC Hum and the beat-frequencies it generates through my speakers is giving me Vertigo. I've modified lines 419 and 461 of entities.lua
from:
volume = 0.5,
to:
volume = 0.01,
and it's much more tolerable, I can still hear them when I'm very close so the sound still serves its function though. Recommend doing this for the next update.