Static-y rumbling?
 

I had my bass in my closet for about a week (tuned waaaay low, to around C) and I took it out, changed the strings and started playing, but im getting a really loud wavy static noise every time i strike a note. I run my guitar through the same amp and it sounds fine, so i assume the problem is with the bass.

I'm a fairly new player and I've never had a problem like this before, can anyone help me out?

This is like trying to dance architecture :hiding:

Active preamp? Try changing the battery.
Weird sound on open strings as well as fretted notes?
Have you checked neck relief?
Bass make/model?