I've been using mine since the beginning of the year and haven't had any problems with it. Since you're not using Hydrofarm's fixture that could be an issue. It could be a bad bulb or a faulty fixture that shortened the life of the bulb. That happened to me twice with another bulb (not CFL) and turned out it was the fixture that was faulty. I also had a new halogen bulb "sizzle up" like you described. I wasn't using the halogen for plants, but my point is, any bulb can burn out prematurely, whether it's a CFL, fluorescent tube, or something else.

If it's only a month old, it still has a one year warranty. Contact the dealer who sold you the bulb for a replacement. And if it happens again, replace the fixture.

make sure your fixture can handle the wattage.

thanks for your comments. The socket is fine with the wattage - actually I have another of the exact same bulb and fixture that has been fine for about 3 months now. But this is the first time I've had a bulb of any kind sizzle up, so I was a bit worried.

It is being treated as a faulty product and the retailer is sending me a replacement, together with a prepaid shipping label to send the broken one back to the manufacture. Love this source.

So... the question is how frequently the bulbs are defective. I guess I'll find out - though I'm still not going to leave them on while I'm out.