Hello people of CTH. I've posted here very occasionally for the past decade or so and you've always been very helpful so thank you again from past Tim.

The problem

My monitor(s) are acting up whenever I use my treadmill. It might sound strange, but I am not crazy. I have a dual monitor setup with a standing desk with a treadmill underneath that I walk on while I'm playing poker. If I'm not walking on the treadmill, the monitors work flawlessly. If I am, they start flickering, shutting on and off, getting discolored, etc.

Here's one screenshot of the monitor getting discolored. If I shut it off and back on it's back to normal.



Here are a couple of GIFs I just took of a monitor flickering and/or shutting off:

https://i.gyazo.com/2f02becf53479dd7...08d6785661.mp4
https://i.gyazo.com/51c2573e6e838987...3c1189e0c7.mp4

Again, this ONLY happens when my treadmill is running. And it seems to get worse as I use more programs/memory; i.e. if I'm playing a bunch of tables it's almost unusable but if I've just started my computer and don't have anything open it's not nearly as bad.

One monitor is a 34" widescreen dell made in 2016 and the other one is a 24" dell which is quite a bit older. The newer one connects via HDMI and the older one connects with an old DVI-D-1 cable which uses a DP converter to plug into my computer. My computer is relatively new and has an i7-6700K with 32gb ram. The graphics card is Radeon RX 480.

Please LMK if there's any additional info I can give that might be helpful in solving the problem.

What I've tried so far

- quadruple checked all of the outlets and cables
- switched the HDMI cables and tried several different outlets
- made sure my graphics card driver is up to date
- made sure no wires/outlets are crossed anywhere
- plugged in different monitors
- tried using only one monitor at a time
- purchased and used a power conditioner
- purchased and used an extension cord to plug the treadmill into an outlet in another room (I checked to make sure the outlet is on a different breaker than my computer/monitor)
- enabled/disabled DP 1.2 and switched between primary and non-primary displays (just clicking buttons at this point)

The only thing I can think of that I haven't tried is replacing my graphics card. But I don't know what to make of the fact that this stuff only happens when I'm walking on the treadmill.

I almost always walk while I'm playing and having to stand/sit still is super tilting so any help would be greatly appreciated.