Bought a new DSL40CR and 91016 footswitch. Amp is great but using it with the 6 position footswitch not so great. Seems to work fine when I first turn it on but if I press #3 or #6 the footswitch lights turn off and it becomes nonfunctional unless I turn the amp off and back on. I also tried a different cable and still no luck. The OEM footswitch seems to work except when plugged in I can not switch channels on the amp but only on the footswitch. Maybe that is normal?