Setup: a desk from IKEA, an iMac 27 2017 staying in the center, Steinberg UR22C connected to the iMac via usb type-c cable, 2 Yamaha HS5 active monitors are connected to the audio interface with balanced TRS-XLR cables staying right from sides of iMac.
The problem: once per around 5-7 minutes some cracking sound (it sounds similar to the one that is produced when you plug in a jack into an amplifier without muting it before, like thrrr-thr, crispy and loud one) pops up.
What's been checked already:
- I've tried to swap L and R monitors, the problem persists on the same side(R), so it's not about some specific monitor
- I've tried to swap the cables, the same result, the problem persists on the same side (R), so it's not cable related problem
- I've disconnected the speaker (R) from the interface at all and it kept producing the weird sound! So it seems to be not related to connection to the interface at all!
- So I left the speaker not connected to the audio interface at all and be only powered. Then I moved the monitor a bit closer to me, so its speaker became not on the same line with iMac, but like 30cm behind of the monitor's speaker and sound disappeared!
- I've tried to change movement direction from horizontal to vertical and lifted the monitor to the same ~30cm (simply put some books under the monitor), but left it on the same line with the iMac and cracking sound persists :(
- The volume of the cracking sound does not depend on volume set on a back side of a monitor as I understand
As for now it looks like a problem is hidden in a bottom right part of iMac (where a power block is situated i guess?) and position of a Yamaha HS5 monitor, but I have no clue what to do next and how to eliminate the problem.