This was the determination of the Apple engineers that heard my audio of same. I am now trying to see if the is the problem by unplugging the dock/drives from the Thunderbolt input. [USB 3.1 into a T-Bolt input] It's an intermittent noise so I'm waiting.
Has anyone else experienced this problem?
Are there better-shielded cables that might mitigate this problem?
Dock is StarTech [ SDOCK2U313] Drives are 4 TB WDs
iMac 21.5″, 12.4
https://www.tripplite.com/usb-2-0-high-speed-a-b-cable-ferrite-chokes-male-3-ft~u023003
You can also buy individual ferrite cores.
No idea if you're familiar with them, but the core reduces certain types of electronic scatter and radiation; it may do what you need.
https://www.tripplite.com/usb-2-0-high-speed-a-b-cable-ferrite-chokes-male-3-ft~u023003
You can also buy individual ferrite cores.
No idea if you're familiar with them, but the core reduces certain types of electronic scatter and radiation; it may do what you need.
My dock has a power supply. The problem 'appears' to be the 'thru-put' of the adapter cable. I've purchased a SuperSpeed adapter and am trying it out as we speak. If I remember I might come back and tell you!
Well, I found my answer! The USB-A to USB-C adapter was not capable of handling the data through-put and the 'road-block' was causing the interference which caused the noise.
One needs a 'SuperSpeed' adapter. In Canada I got mine from Canada Computer which manufactures the 'ICAN' brand. In the sates the 'J5tech' makes similar items.
Thanks to all who helped.
Your dock may be the problem, try another one that has its own power supply that is adequate to support all the peripherals that you plug into it.
USB external drives./dock creating noise from iMac.
