I have a set of Sennheiser HD-590's that use a 2.5mm -> 3.5mm detachable cable which can be replaced very easily. Had them for 7 years and replaced the cable twice, the second time I just got a 2.5mm -> 3.5mm adapter and a regular 3.5mm cable because its pretty hard to find a 2.5mm -> 3.5mm...

Yes cheap earbuds work fine, simply playing around with the cable does nothing with any reliability. Plugging them into the TV seems to fix them immediately then I can plug them back into the PC and they will work fine from anywhere from a few minutes to a few hours.    

About a month ago the right cup just died on my Sennheiser PC-350s so I sent them back on warranty. They came back a few days ago with a note saying they tested just fine and there is nothing wrong with them, but there is something wrong with them. (I think)   Whenever I use them on my PC...

In case anyone is searching for the same question in the future Sennheiser Canada will repair it under warranty no questions asked as long as you have a receipt.

I don't know how but I somehow managed to get a perfect clean cut on the headphone cable of my PC 350's, the mic cable is in perfect condition though. Will Sennheiser Canada fix this under warranty? I sent them a support request over a day ago on their website with no reply and their support...