I'm getting static over the pi's composite audio (currently through an amp, but happens with other amps, a computer, and even headphones).
I thought the 3.5mm jack cable was the issue (3 pole vs 4), but I've removed that by going back to an rpi B model.
It seems the cause is buried somewhere when I updated raspbian to work with the model B+, giving the illusion that it was the model B+ itself (as I had no reason to update when on the model B and was keeping separate sd cards).
How I am playing audio is through python and pygame. Simply calling
import pygame pygame.mixer.init()
is enough to trigger the static/noise. Stopping pygame stops the static/noise.
The version of pygame is 1.9.1 release and I'm using python 2.7.3.
Checking python 3.2.3 and pygame '1.9.2a0' also results in the same issue.