Directed advertisement times out instantly after powering up nRF5340 Audio DK

[SohamGhugare]

Hey Team,

Whenever we flash the audio application (from the official samples provided) on a development board and leave the board unpowered/unattended for 10-15 days, the bluetooth advertisement messes up and doesn't let us connect any mobile device to the board. Precisely, right after powering the board, we get a message saying "Directed adv timed out with no connection, reverting to normal adv" in the RTT logs. This does not let us connect/pair any mobile device to the board. The quickest way to fix this is to simply re-flash the same audio application and it works perfectly fine. After re-flashing, we don't get the "Directed adv timed out..." error again and the board connects smoothly to the mobile device. 

I have attached a detailed video about this below

Video Link

Below is an image showing the logs after connecting the Audio DK (see the third last line for the unusual error)

Regards,

Soham

[Elfving]

Hi Soham, 

That is odd. Especially since nothing immediately comes to mind as what leaving it off for two weeks can do to it. Besides maybe what could happen on the phone side - is this the same phone that it was connected to earlier?

Does removing the bonding info help?

Did you see this with multiple boards or just the one? 

Directed adv timed out with no connection, reverting to normal adv

Did you not get this before?

Could you get the logs from the attempted connection from this? Getting more logs on the nRF would also be nice, but as that requires flashing it again with something and then waiting for 2 weeks, I guess that is not an option.

Regards,

Elfving

[SohamGhugare]

Hi Elfving,

Yes we have tried it on around 4 different nRF5340 Audio DKs and this happens on every single one of them. I haven't tried removing the bonding info, but now I might have to leave the board unpowered for a few days to test this. 

Elfving said:

is this the same phone that it was connected to earlier?

Yes its the same phone. 

Elfving said:

Could you get the logs from the attempted connection from this?

Yes but as I said above, I might have to wait a few days before testing this again. I'm trying to get as much info as possible on this as its hindering our production significantly. Will let you know any other details I receive but I would be really grateful if I could get any idea from Nordic's tech team as well.

Regards,

Soham

[Elfving]

Sure thing. If you are willing to wait for a few more days to test this, it would also be an idea to enable more logging on the nRF. Getting some more logs is the best way forward either way.

What sort of phone is being used here?

[SohamGhugare]

The mobile phone used was Samsung S24.

Can you tell me how can i enable more logging on the nRF?

[Elfving]

If you could eg. set CONFIG_LOG_DEFAULT_LEVEL=3 that would be nice.

And maybe CONFIG_BT_LOG_LEVEL_DBG=y

For more info see here.

What NCS version are you using btw? I see that there has been some fixes regarding the advertising here, but this should be fixed after 2.7. I generally recommend using the newest tagged NCS version for Audio, as there is a lot of development in that area.

Regards,

Elfving

[SohamGhugare]

Sure, I will set the configs before testing, thanks for sharing.

I'm using NCS v3.0.1 (both toolchain and SDK)

Regards,

Soham