On further thought, the problem may be back at the meter, power entrance panel. Old houses tend to have loosened feeder screws in the meter housing.
Might call local power provider to check connections at meter, You need them to cut and re-install seal on meter housing.
At one of my old houses, when a neighbor's AC powered on, my lights dimmed. Power company had pulled meter, took several turns on the screwdriver to tighten feeder connection. Dimming problem solved.
There must be moderation in everything, including moderation.