Xm4 hiss with noise cancelling?

[Ainsley001]

I bought the new XM4  headphones to replace a pair of Bose QC 35 but the noise cancelling on full produces a background hiss.

This isn’t the hiss in one ear cup that some other people have referred to as a fault, this is general background hiss across both ears, very low level but audible enough to be annoying. 

the QC 35s didnt do this and i tried a pair of Bose 700s to compare and they didn't produce this either. Did i just get a faulty pair or this a function of the NC on the Sonys?

Thanks

[Joe_Dohn]

There's definitely audible feedback from any NC circuit if you're in a quiet environment, that's why it's generally recommended to only enable NC if there is background noise that needs to be cancelled.

That said, does this happen with all devices and tracks? Are you also on the latest software version?

- J.D.

[TJWhiteStar]

I started getting a "Listening to the Ocean in a shell" type noise in mine and it was easily solved by just putting some Silica Gel packets in the ear cups when I put them away in the case.

It seems the issue was caused by the small amount of moisture that was in the air or from light sweating. Maybe Sony's ANC is really sensitive to this inside the earcups?

Either way don't have those issues now by doing this. Might be worth a try before returning them.