I've had this problem now with 3 different rifts.
Support were very helpful and replaced the units quickly.
The first two lasted about 5/6 months before the audio broke, but my last one barely lasted 2 months. I haven't even bothered to contact support this time as I've had enough of the whole design fault.
I'm now just using my own headphones with the rift. I love my rift and I had recommended buying one to several of my friends in the past. I really can't support them or recommend this product now I know this breakage is so common. Which frankly saddens me after supprting Oculus from the beginning.
A www.. 14 days after my 2 year warranty ran out, and now I'm sure the infamous loose connection in the strap happened to me too
How is that even possible? The CV1 hasn't been available for two years. It was first released in spring 2016!