So I've been going crazy trying to hunt down the hum in my turntable set up. The hum only appears between songs and on piano ballads. Any thing with acoustic guitars and the him seems to fade away. I've got the ground wire connected between the preamp and turntable using Pro-Ject's stock wires. Here are the suspects:
Bellari VP130: Hum has been reported in several reviews of this Preamp but supposedly it disappears with an Enercell 15v 1A power supply. The first Enercell power supply I used worked sporadically and when it first refused to power the unit I stupidly switched to the incorrect polarity. I fear this may be the cause of the hum now. I switched to a working power supply and it powers the unit but the hum isn't different from the stock wall wart.
Pro-Ject Audio Debut Carbon: The hum becomes more severe when my fingers are near the cartridge and the slip mat has a significant static charge since it always comes off with my vinyl. The hum also goes away when I unplug the inputs in the preamp.
Etymotic ER6i: When I swapped to Apple's garbage EarPods I couldn't hear any hum even with the volume maxed out but that could be due to the poor quality.
Power Strip: It's a cheap Best Buy strip and my building was built in the 1800s.
Thank you for any help you can offer!