How to fix 'static' noise on Bose QC20i Noise Cancelling Headphones?
I have a pair of Bose QC20i noise cancellation headphones. When they were new, I could turn on the noise cancellation switch without the jack being plugged in, and they worked fine.
Now, they produce a noticeable feedback sound when not plugged in. This can be altered by touching the tip of the headphone jack.
When plugged in, the feedback goes away, but they produce a hissing sound in the left ear. Sometimes this hissing replaces the feedback sound mentioned above.
However, when music is turned on, even at a level which is inaudible to me, they seem to work fine.
I bought them new only a few months ago, but the purchase was on ebay so Bose tells me they will not honor the warranty.
Does this sound like something I could try to fix myself?
Any hints on troubleshooting would be appreciated.