Filter does not work: dead SID chip?

[Explodicide]

Heya,

I just bought a sammichSID off a friend, and I'm having some issues with the audio. 

It arrived this weekend, and I fired it up to test it.  For the most part it sounds fantastic (srsly in love with this little box).  But I noticed 2 things:  on any of the Poly patches half of the notes are coming though at about half volume, and with what sounds like a mostly closed filter compared to the other notes.  The other thing is that the drum patches sound weird on about half the notes as well.  It seems like half the drum sounds are what I would expect, and the others are just weak soft tones that don't sound like much at all.  

According to the LEDs, all of the weak notes are coming from the voices on the right chip.  

To test things out I fired up Ctrlr and started messing around with things.  The left 3 oscillators seem to work normally (to me, anyways) but when I enable any of the filters for the right OSCs, it's acting like the filter is permanently stuck in low-pass mode, and adjusting the cutoff value does nothing.  The volume of notes is severely reduced, and the notes just sound weak overall.  

Does this sound like a dead SID chip?  That's what my instincts are telling me, since the left voices sound fine and react normally.  Maybe one was a fake SID?

According to my friend it was made by a boutique shop (Lowgain Electronics) so I wouldn't assume that it's a fake chip.  Maybe it just got damaged in shipping.  

Thanks for any input you can give me on this.  I can run additional tests if needed.

[Altitude]

that sounds like a broken sid chip, dead filter is the most common failure i've seen

[Explodicide]

Cool, thanks for the confirmation.  

Somewhat annoying, but I got the Sammich at a pretty good price, so this isn't the end of the world.  I managed to snag an auction for a pair of SIDs on eBay just now, so I'll have one to swap in for the busted one, and one as a spare just in case.  

[Altitude]

make sure you test them when you get them

[Explodicide]

Duly noted.  I'll spend my time while they're shipping to me reading the manual and running some tests on my current chips, so I'm ready to test them when they get here.  

Thanks!