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macrumors newbie
Original poster
Oct 7, 2021
I'm experiencing an inconsistent pop/click when using my new AKG k371-BT bluetooth headphones. This happens on both Spotify and YouTube. This didn't happen with my Beats Solo3 Bluetooth headphones and it doesn't happen with the built-in speakers either. Plugging the new headphones in with a cable also works fine. Therefore, this is some sort of compatability issue between the macbook/bluetooth/headphones.

The sound is very inconsistent and I wonder if it has something to do with codecs/aac/aptx or pairing issues.

I've ran bluetoothd in console and this came out when I switch on the headphones:

2021-10-07 11:09:14.740 bluetoothd[2209:335455] [establishKernelConnection] Received an error from IOServiceOpen() - 0xe00002c7.  NULLing out io_service_t.
2021-10-07 11:09:15.132 bluetoothd[2209:335455]  [DaemonHandleLinkKeyRequest]
2021-10-07 11:09:15.133 bluetoothd[2209:335455]  [HandleLinkKeyRequest] we don't have a link key for that device.
2021-10-07 11:09:15.136 bluetoothd[2209:335455]  [HandleLinkKeyRequest] Exiting with result: 0x0.
2021-10-07 11:09:15.795 bluetoothd[2209:335455]  [DaemonHandleLinkKeyRequest]
2021-10-07 11:09:15.796 bluetoothd[2209:335455]  [HandleLinkKeyRequest] we don't have a link key for that device.
2021-10-07 11:09:15.806 bluetoothd[2209:335455]  [HandleLinkKeyRequest] Exiting with result: 0x0.

Alot of stuff online states to download Bluetooth Explorer and toggle the AAC/APTX settings, but I can't even get that to download as the apple dev site just sends me to a contact us page.

I've paired the headphones to my iPhone and they work fine. So this issue seems to be with the macbook pro (15-inch, mid 2015) running BigSur 11.6

Sound Preference show Format is set to "2-ch 32bit Float 48Khz" and I only have one other option of 16bit, which is really bad sounding.

Can anyone offer some suggestions on how to fix this problem? It's really annoying as I was looking forward to enjoying my new headphones.
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