Hey all, This is my first post, and for unfortunate reasons, but I'm having some amp/cab issues that just kicked up at my last show. I was mid song at what I thought were very reasonable levels and all of a sudden my speakers started crackling at certain frequencies (low G, for example), and sometimes cutting out altogether until I fidgeted with the gain knob a bit. All the while, i heard that it sounded alright in the house. I'm running an Ampeg PF-500 through a 4 ohm Avatar 4x10, and I'm not really sure where to start eliminating issues. Made me feel like an idiot on stage so I'd love to have a better understanding in case something like this happens again.