I've switched my phone over to the LV profile with limits set to 125/900 (since according to kernel-config show this puts the DSP at 500 vs 430), and now i don't appear to be getting the static when testing with headphones (vs the speakers i have at work), but now it is playing the alert sound through both the headphones and through the external speakers. I don't mind this since it ensures you hear it if you have your ear buds out as well as if you have them in.

But it's interesting behavior that i thought you might want to look into. My guess is that it has to do with the DSP speeds.