I also recently bought a USB enclosure for my external drive. I didn't notice this noise interference in the past when I was running the external HDD without a case. This external enclosure DOES NOT have any type of fan inside. That's not the issue because it's simply the metal case with the HDD connected inside.
I do have a pretty noisy jtag due to the fan mods. However, this what I call beeping noise can be heard overtop of the fans. I have a custom made falcon jtag 360. The system works well overall but this noise interference is not only annoying but concerning as well. Does anybody have any ideas as to what this is about? Thanks!
BTW, I can't really tell where the noise is coming from. Seems to be the HDD but I have it setting close to the console so can't rule out the console making this noise either. I have pretty short power & USB cable cords.