Hey. I own a Gallien Krueger 1001RB-II with two GK Neo 212 cabs. I´ve owned this for a long time. My main bass is a Modulus Flea with LP pickup and OBP-1 18V preamp. The setup has been working really great the last year, gigged a lot with it and played a lot with it. At the band practice today I got an awful farting sound when played at higher volumes. It`s a nice sound as long as I am keeping the volume under 9 O´clock. All the EQ are 12 O´clock and boost and woofer is at a very low stage. If Im play any louder it beginning to fart. I´ve tried another cable, change the batteries in my Modulus and no difference. I´ve tried an EBS 350 amp on the cabs and it´s a lot better, but the amp is a lot less powerful. I also tried my GK 1001 on a EBS cab and its awful. It´s so hard to troubleshoot it, and I need some help from you guys. Is it possible that my amp is not working, but cabs do?