headphones reseting themselves

This can occur for a number of reasons. First off, either the plug or the internal connection could be loose, broken, dirty or corroded. The wiring from the phones to the connection at the PC may have a break (cats like to chew on them as well a rodents). To check the wire just do a visual check very closely. For the plug and receiving connection try to make it disconnect by wiggling to see it you have an issue there.
Often headphone wires become broken right where the wire reaches the plug since they tend to get bent a lot there and you know what can happen when a wire is repeatedly bent over and over again at one spot right? The last thing you might try if the others get you nowhere is to try a manual cleaning of the plug and slot. The plug is easy and you can see if it's corroded or has gunked up, the slot is a little more difficult since you can't get inside easily but a repeated plugging in and out over and over can often clean the contacts inside simply by friction. Whether your dealing with stereo jack type headphone or a USB, many of the same reasons for disconnection can occur.

Using a different headphone doesn't eliminate the socket from being a problem though. Then there is also the possibility that the problem is where the jack connects to the board. If your using the case front jack and you have been inside cleaning, you might have loosened the connector at the board.

If your using the back of the PC that shouldn't be an issue but most boards do not have a headphone jack in the back. You could hook it up to the line out and test there but to be safe turn your volume all the way down before plugging in the phones since they require a lot less power than speakers and you don't want to damage them.

Have you looked in Device Manager for an audio problem? The only other and very slim possibility I can think of in the physical realm would be a cracked solder joint. If your speakers do not disconnect just the headphones that is a clue as well.