Fix for Sirius Static

I may or may not have static. I bought a 2006 which has aftermarket Sirus as installed by Longo Toyota. I'm assuming it's the same DEI unit that everyone else has, but will have to check to be sure. There's a large black box near the rearview mirror which I assume is only hiding the antenna, and that the electronics are behind the glovebox somewhere (wonder if that's what I hear rattling...)

Anyway, the left (driver's) side tweeter sounds funky, like a bad speaker. I was all set to replace the speaker until I realized it doesn't make this sound under AM or FM, only SAT. And, it's only on the left channel, not the right. I'm not sure if the lower door speaker (mid/woofer) also has this noise, I have yet to stick my head down there.

I've tried the audio "boost" code that's been posted, and didn't really notice a difference, so I'm wondering if I could have a different unit perhaps?

 

I'm still having the same issue and have not had time to take the dash apart to find the unit. Is there another way to check perhaps? Hoping there's an upgrade I can do without spending a fortune.