turntable + fluorescent light = crackling speakers
This is my first post here and I'm hoping someone may be able to help with a strange problem I'm having. I am setting up a turntable (used Micro-Seiki) for the first time with a Cambridge Audio 540P phono pre-amp. The turntable ground wire is attached to the ground post on the 540P, and the turntable and 540P are plugged into a power bar. A fluorescent desk light is also plugged into the same powerbar to light up the turntable.
When I turned on the light for the first time, and it flickered to life, I heard a horrible crackling coming from my speakers. The crackling stopped after the light stopped flickering and stayed on. My Simaudio i5 integrated amp was on stand-by and it is plugged into a Xindak XF-2000 power filter that is plugged into the same outlet as the powerbar for the light and turntable. After I check the outlet with a circuit tester to ensure it was installed and grounded properly, I started unplugging things to see where the problem was. Eventually I unplugged the turntable and I could turn on the fluorescent light without the crackling.
Could this be a problem with the turntable, perhaps the ground? Is there a way to test it, or could something else be causing this? Or is this just a bad combination of items to be using together?
While I was testing things and listening closely to my speakers, I also noticed a very low hum coming from the speakers even when the amp was on stand-by and all the stuff above was unplugged. It is barely audible unless I put my ear right up to the speaker, and may have been there before I noticed this other problem. Is this very low hum normal when an integrated amp is on or in stand-by?
Thanks for any advice,