--- Update 2/28/15:
The problem seems to be radio interference that USB 3.0 hard drives emit.
http://www.macobserver.com/tmo/article/usb-3.0-hard-drives-can-cause-wi-fi-interference
Indeed, I had my HDs real close, sometimes on top of the Mini. Got myself a USB hub and put some space between HDs and the Mini, and the WIFI seems much more responsive now.
--- Old Post:
The Mac Mini's (2012) WiFi slows down considerably when too many USB peripherals are attached.
I had all 4 USB connectors populated when I started noticing real sluggishness.
Typically with Safari pages start to load, but get stuck in the middle and nothing happens. Progress is halted, pages stay blank.
I removed 2 out of 4 USB peripherals, and bam! All peppy was the Mini again.
Is too much USB power draw affecting WiFI?
