Power Amp or Cabinet Problem?

[mynameisjack2]

Lately, when I use my amp set up (VTD -> Peavey IPR 1600 -> SWR Triad), sometimes I'll get this almost rattling distortion sound. It's not all the time, but when it's there it's incredibly noticeable. I replaced the 10" Speaker pretty recently, so I'm reasonably confident the speaker isn't blown (though that originally fixed the problem)

Any ideas on what could be the issue?

[BassmanPaul]

What did you replace the old driver with???

[mynameisjack2]

Eminence Delta 10A

[will33]

Process of elimination...try different amp/cab. Go through make sure all the screws are tight. Make sure there isn't a wire ratting against the back of the cone on the inside.