Hi Jimmy, I have been an electrician for about 8 years now and yes, a ballast will sometimes give off a smell when u first fire them up. Mostly they smell kinda like they are burning off some oil or something, but for a week that in my exp. is not common. If u could maybe try and explain the smell and the type of setup its in (ie. hood, free air, ect.) and the type and where u got them from. Also if they are magnetic ballasts or electronic. I have 2 400 watt MH over my tank and they did smell for a few hours but thats it. Lemi know all ur info and I'll c what I can find out, if it comes down 2 it and ur not 2 far from me I could come and take a look at them for ya.