Kevin, I'm having the same problems with the QSC K12 and my POD HD500X. When I'm in a live situation - at times, even at rehearsals - I can't hear myself. Are you saying that by switching from XLR to 1/4'' you solved the volume problem? I'm gonna try this tonight. Hope it works, cause if not, I'll sell the active monitor and buy myself a amp or a good in-ear system.