I had posted similar topic in live sound, just hoping more people will see it here. I have been having issue with my set up (GKMB800 + GKNeo4x10) in only one place - our jam space. We rent a pretty tiny room - 1bass /1guitar/ drums /vocals. I started to notice my sound volume would all of a sudden degrade and become way lower, and even distorted at certain times. The issue would go away on its own. That got me really concerned i might have a blown speaker, or damaged amp. But anywhere else i play it sounds just fine! I brought my setup to the music store, where i got it, and they tested it whole day and never saw an issue. What i realized later, my problem would start - almost at the same time the super loud metal band would go full blast next door... And i am plugged in likely to the same grid they are... I think requirements are 120v @ 15amp that should give me 1800Watt more than enough. This idea with power grid issue came in mind after i read GK manual where they mention, not to have anything with a lot of power draw plugged in the same grid. Any one here experienced issues with lower volume .. all of a sudden distortion / break up related to not enough juice / power / volts in the power grid???