Hey all, been having an internment noise issue in my system (most audible in my phono rig due to gain) related to my AC/hot air blower kicking on/off as part of its regular operation. I was wondering if anyone here has dealt with something similar and could offer advice. As stated in the thread title I’m in an apartment and have little control over my environment. Currently my stereo is plugged into a Tripp-Lite IsoBar > outlet. Unfortunately this is beside the ancient thermostat controller and blower unit itself. When playing records (VM95ML>Darlington Labs MP-7>Yamaha A-S501) if the AC unit kicks on / off there is often a pop through the speakers about the volume of a moderate surface tick — pretty annoying. I used my cheapo multimeter and manually toggled the AC unit on/off measured some surging up to 135v+, and even in some instances browning out down to 113v on the outlet the stereo is plugged into, and all other outlets in the room on the line. I’m pretty certain this is the source of the issue but of course I’m unable to relocate the stereo. My main two options seem to be: - Run an extension cable about 40’ to the outlet in the back of the room which is on the bedroom’s line and doesn’t seem to fluctuate in voltage. Doesn’t seem ideal with the long cord but that way the stereo is isolated from the issue which would possibly seem to be a risk of damage. Unfortunately this outlet is switched and shared with a Roomba which also isn’t ideal. - Pursue some sort of isolation between this current line and my stereo, possibly an isolation transformer? I’m totally uneducated about these power conditioning / isolating products. Obviously welcome any and all suggestions but I’m primarily looking to treat the issue as pragmatically as possible, for this mostly mid-fi setup, no isolation esoterica in the budget. Thanks for any help!