Just thought I'd share withn you, that you CAN get magnetic ballasts that are switchable from HPS to MH. Ihave 4 of em right now. XTRA SUN brand. If your gonna grow weed indoors, you gotta get the good stuff, you buy cheap, you get cheap. I tried to0 tell mt little bro that, and he went and bought and cheap digi ballasts online, and they lasted 2 rounds and were broken. Sounds like the ones you bought were the cheapest miserable Chinese made crap on the market, and there's lots of it out there. Good way to burn your house down too.