First of all there are no brushes in an AC induction motor. The washing machine has some digital timer and control circuits that are notorious hash generators.
Question for Encryption and Ch1, when in Comcast or anyone else's territory what alternative do you have? Is not a monopoly the only game in town?
"We're currently the only tenants drawing from the splitter."
Maybe you can explain that, what would it be doing in YOUR line unless you signed up for more than a one set connection? Maybe someone was pirating TV before you moved in and the installer simply connected you at the pole and never came in the building and noticed it? What does the other side feed and where does it go? You may be looking at signal loss and leakage here AND a legal liability so I'd make darn sure it's on the up and up.
I'd get Larry the cable guy in to fix the problem by whatever means necessary and let Comcast determine what means are necessary. They're under contract and have a legal responsibility to provide good reliable service. Call customer service, explain the problem and NOT your idea of how to fix it in SIMPLE and concise language (remember you're dealing with a moron) and have him/her write up the work order accordingly. Should you happen to speak to the cable guy remember you're dealing with another moron; he's an installer, not an engineer. Again do NOT tell him anything of your ideas, he does NOT like being told what to do!
BTW, don't count on even seeing Larry when he shows up eventually at a time you least expect; he'll follow what's on the work order to the letter without taking any more steps that he needs to complete the job AS ORDERED. He's paid by the job and not by time on the job so he'll get in and out as quickly as possible and move on to the next job. Quantity and not quality is job one in his eyes; that's how to make money, not by messing around with some schlep that means nothing to his paycheck.
Why Larry? He's the cable guy with the "git 'er done" attitude... right? Ryan, just one last thought. You sure have your problems don't you? Every time you post it's always something; I'm going to start calling you The Hard Luck Kid. I know another Ryan and it never fails, that name must be jinxed so you may consider changing it and having an exorcism performed. (;->)