This ballast has only been running for 2 weeks at 6 hours/day and almost every day one of the bulbs this ballast is running will turn off. Sometimes both of them turn off, and they don't come back on. The only way I've been able to get them to come back on is to unplug the ballast and let it sit for a couple minutes. Now I know this isn't normal, but has anyone else run across this problem?