QC30 hissing sound

[akj]

I just bought a pair of QC30. When I turn down noise cancellation, I hear white noise/hissing that keeps getting louder as I turn down the ANC. It is not the background noise of the room, because if I switch off the headphones the white noise disappears. 

It does not matter whether I am playing anything or not through the headphones. The white noise persists.

Is this normal or did I get a defective piece? 

The date of manufacture of the headphones is July 13, 2017. 

I have upgraded to the latest firmware 2.5.3.

[Mohsin_S]

Hi akj,

Thank you for reaching out! In extremely quiet environments it is possible to hear the noise floor of the active electronics, this may be perceived as a low-level hiss or hum. This is normal operation of the headset. 

Hope that helps. Feel free to reach out if there is anything else you need. 

Take care,

Mohsin - Community Support

[boseuser2]

I just got a pair of QC30s. Even when in a quiet room when the volume on my phone is turned all the way and the noise cancelling on the bose connect app is turned all the way down, I hear a static sound from the QC30. It decreases as I increase the amount of noise cancelling.

It is as if the earphones are actually feeding the surrounding sound into my ears fro the microphones. It reminds me earbuds that form a seal but have a "hearthrough" mode, like the Jabra 65t. Is this normal behavior or is the set defective? Is there a way to disable it completely, so that they simply behave like regular wireless earphones? Sometimes I would like to listen to music without any noise cancelling and the static sound is annoying. 

[boseuser2]

I found that this question was asked before:

https://community.bose.com/t5/Headphones-Archive/QC30-hissing-sound/td-p/143275

Thank you for reaching out! In extremely quiet environments it is possible to hear the noise floor of the active electronics, this may be perceived as a low-level hiss or hum. This is normal operation of the headset. 

However, this happens even when the volume and the sound cancelling is turned off, so the active noise cancelling electronics should not be doing anything... In short, I'd like to know why this behavior is present in my earphones, and how to disable it and just use them as normal wireless earphones without any ANC - like the soundsport wireless, for instance. 

[boseuser2]

Thanks for your reply. That’s what it said in the other post but this noise is only perceptible when the noise cancelling is off, even when the volume down.

Why would i be able to hear it when it’s off but not on? I would like to be able to use the headset with noise cancelling off with out having to deal with the noise.

[Greg_B]

Hello boseuser2,

Thank you for posting. In extremely quiet environments it is possible to hear the noise floor of the active electronics, this may be perceived as a low-level hiss or hum. This is normal operation of the headset. If you are concerned that you're headphones are malfunctioning, you can always reach out to our Customer Support team here. Just select your region, and kindly scroll down to where you see "Contact Us".

Best Regards,

Greg - Community Support