The power strip itself works fine. However, after one year of thinking that my Yamaha monitors were picking up EM interference or something, I realized that 90% of the annoying beeping/buzzing noises I'd been hearing came from the power strip all along. Specifically – from the USB ports. When nothing is connected, they produce a whining, screeching electrical noise (well below speaking-level but audible enough to be extremely frustrating in a home studio environment). As soon as you connect a phone or other usb-charging device however, it stops.
I believe this should either be fixed asap or at least included in the description to notify people of the issue. If you don't feel like buying and frying a spare phone/other device with a li-ion battery by keeping it connected to the strip 24/7, then I suggest you buy a more expensive power strip or one without the USB-ports.