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I believe this dude is having the same issue with his equipment
Posted: 02 Jul 2022, 11:05
by Thatweirdinputlag
In short, this guy has about 5 videos on him struggling with static/dirty noise coming from his outlets because of his iMac. He goes on and finally finds where the issue was coming from, it was the iMac's old power supply, he changes it and the sound is gone! Little did he know, it all came back 2 weeks after. Rings any bells?
Check out his other videos in the same timeline.
https://youtu.be/d6hcjVPMBE0
Re: I believe this dude is having the same issue with his equipment
Posted: 06 Jul 2022, 15:57
by Chief Blur Buster
This is the nature of trying to troubleshoot this.
It's many wild goose chases and many red herrings. Sometimes it's simple things as moving a wire 1 inch this way or that way -- even a power brick moving 1 inch closer to a data cable. Or bad interference damaged the EMI-rejecting circuits of the power supply really fast. Hard to say.
All the troubleshooting often inevitably accidentally fixes other things (e.g. moving inteference sources one or two inches away from being a problem).
Inverse square law is your best friend, keep power cables & power bricks & gadgets (e.g. routers) away from electronics (don't put a router near your computer).
Small inteference is easily solved with a few millimeters or an inch of distance (e.g. accidentally moving a USB cable further away from crossing past a big power supply, big interference may be impossible to solve (e.g. living under a high voltage power transmission line).
You do one thing but while you were doing it, you accidentally solved the problem with something else (e.g. replacing the PSU forced you to reorganize your cables slightly). And you co-relate to the wrong solution. Then the problem keeps coming back because you thought you solved the problem.
It is also wholly possible that it is something else too entirely, like a computer automatically switching on/off various modes (e.g. like switching from fastpath to interleave on DSL). Even PCIe and DisplayPort and USB can slightly change modulation protocols to resist interference better, like automatically going down to DisplayPort 1.2 bitrates instead of DisplayPort 2.0 bitrates -- in theory.
The modulation-demodulation protocols over accessory cables are like ultrashort versions of a long DSL line, and are subject to latency changes from protocol changes too. Often a computer power cycle (including monitor) and/or an OS reinstall often resets to the fastest protocols used, resetting the problem yet again. Targetting the root cause and/or protocol locking is horrendously complex and is typically not even possible at all due to the very blackbox nature of these accessory-data-wire prototcols (whether USB or video cables).
This also applies to circuit paths (e.g. data protocols used on PCIe circuit lines), internal cables like SATA or USB headers, and other ultra high speed internal data transmissions (pins from GPU to GDDR6 memory) that runs at very tight noise margins in a high-interference regime.
Intermittent problems (going away and coming back) is one of the hardest problems to diagnose.
Re: I believe this dude is having the same issue with his equipment
Posted: 07 Jul 2022, 02:38
by Thatweirdinputlag
Chief Blur Buster wrote: ↑06 Jul 2022, 15:57
This is the nature of trying to troubleshoot this.
It's many wild goose chases and many red herrings. Sometimes it's simple things as moving a wire 1 inch this way or that way -- even a power brick moving 1 inch closer to a data cable. Or bad interference damaged the EMI-rejecting circuits of the power supply really fast. Hard to say.
All the troubleshooting often inevitably accidentally fixes other things (e.g. moving inteference sources one or two inches away from being a problem).
Inverse square law is your best friend, keep power cables & power bricks & gadgets (e.g. routers) away from electronics (don't put a router near your computer).
Small inteference is easily solved with a few millimeters or an inch of distance (e.g. accidentally moving a USB cable further away from crossing past a big power supply, big interference may be impossible to solve (e.g. living under a high voltage power transmission line).
You do one thing but while you were doing it, you accidentally solved the problem with something else (e.g. replacing the PSU forced you to reorganize your cables slightly). And you co-relate to the wrong solution. Then the problem keeps coming back because you thought you solved the problem.
It is also wholly possible that it is something else too entirely, like a computer automatically switching on/off various modes (e.g. like switching from fastpath to interleave on DSL). Even PCIe and DisplayPort and USB can slightly change modulation protocols to resist interference better, like automatically going down to DisplayPort 1.2 bitrates instead of DisplayPort 2.0 bitrates -- in theory.
The modulation-demodulation protocols over accessory cables are like ultrashort versions of a long DSL line, and are subject to latency changes from protocol changes too. Often a computer power cycle (including monitor) and/or an OS reinstall often resets to the fastest protocols used, resetting the problem yet again. Targetting the root cause and/or protocol locking is horrendously complex and is typically not even possible at all due to the very blackbox nature of these accessory-data-wire prototcols (whether USB or video cables).
This also applies to circuit paths (e.g. data protocols used on PCIe circuit lines), internal cables like SATA or USB headers, and other ultra high speed internal data transmissions (pins from GPU to GDDR6 memory) that runs at very tight noise margins in a high-interference regime.
Intermittent problems (going away and coming back) is one of the hardest problems to diagnose.
Yep, a wild goose. Even more like chasing a mirage! You always think you're close, but you never really are. I'm going to comment on that guys last video and see if he found anything else on this issue, he's more of a musician/audiophile and not a gamer. I watched his video randomly when I was going through some research on power conditioners, Furman to be exact. What go me hooked was the fact that after finding out it was his iMac that is making the noise, he put the iMac on an entirely different circuit from his amplifiers and the static buzz-like sound was still present. Even a power conditioner wasn't enough to take out the noise.
Anyhow, thanks for the reply Chief! I will update this post if he replies.
P.S. Really glad that you have updated the rules of this sub-forum btw! But we all know that people hate reading, hopefully though it saves a poor soul's pocket from falling into the trap of trying every "possible" fix hopelessly thinking it'd be his/her salvation.
Re: I believe this dude is having the same issue with his equipment
Posted: 10 Jul 2022, 03:35
by Thatweirdinputlag
Update to this post, the man owning that youtube channel replied:
" I never solved the problem. I gave the computer to my wife and we moved it into another room and it still makes the noise in my guitar room. Crazy. I bought a new iMac with the smaller monitor and I don't have the problem. It is in my guitar room. I think the power supply of that large 27" monitor is what causes the problem. When I want silence during recording, I have to shut down this old Mac AND unplug it.
My new iMac has the smaller 17" monitor. I didn't want to have the same problem so I got the smaller monitor thinking that was what was causing the problem. It's been good for several years now.
Actually, the new Mac has a 21.5" monitor. I just looked at the new iMac with the 24" very thin monitor and it looks pretty cool. I might eventually get one and retire this big one altogether. "
So apparently even after changing the old power supply for a new one, the weird sound came back 2 weeks after. The only thing that solves it is by him shutting down that old iMac and unplugging it completely.