I am currently struggling with the issue of the Bluetooth board disconnecting in irregular intervals ranging from 30 seconds to 10 minutes. The disconnection message is reason 8 for these disconnects.
I thought originally that the issue was because my bluetooth board did not have a 32.768kHz clock attached and was instead using the RC with the 500ppm setting, so I had a second revision of the board made with a 32.768kHz clock but the issue still occurred with the usage of the 32.768kHz clock.
Some additional details that may be relevant: The chip is actively using usb through out the duration of its run time. I'm using the the third-party component E73-2G4M08S1C which uses nRF52840 revision 2.0 (it shows on visual studio code as NRF52840_xxAA_REV2 which I assume means that it is revision 2.0).
Thank you