No sound on my second Raspberry Pi4 with my multiroom setup - (Alsa) Failed to get chunk

I have two Raspberry Pi 4, one with 4 GB of RAM, and the other with 2 GB of RAM. I use Balena Sound for multi-room broadcasting. The Raspberry PI with 4 GB RAM is the “master” computer, the one with 2 GB RAM is the “slave” computer. On these two machines, I installed with the “production” edition the OS balena OS 2.83.10+rev1, Supervisor version 12.9.3. I transmit my music with an Android smartphone via a Blue Tooth Tp-Link UB400 dongle, which is connected to the “master” computer, the Raspberry PI with 4 GB of RAM. I use the simple audio output of the Raspberries to listen to the sound.
When I turn it on, everything works fine, but after a while, the “slave” computer does not emit any sound. Looking at the terminal of this computer via the balena dashboard, there is informations such as :

multiroom-client 2021-10-26 16-50-34 [Info] (getPlayerChunk) Exception

  • multiroom-client 2021-10-26 16-50-34 [Info] (Alsa) Failed to get chunk*
  • multiroom-client 2021-10-26 16-50-39 [Notice] (Alsa) No chunk received for 5000ms. Closing ALSA.*
  • multiroom-server 2021-10-26 16-52-17 [Info] (do_read) next read < 0 (balenaSound): -14.886 ms*
  • multiroom-client 2021-10-26 16-57-00 [Info] (setDiffToServer) Last time sync older than a minute. Clearing time buffer*
  • multiroom-client 2021-10-26 16-57-00 [Info] (Alsa) frames: 1323*
  • multiroom-client 2021-10-26 16-57-00 [Warn] (Alsa) snd_pcm_avail_delay failed: I/O error, avail: 2645, delay: 5249, retrying.*
  • multiroom-client 2021-10-26 16-57-00 [Info] (Alsa) Failed to get chunk*
  • multiroom-client 2021-10-26 16-57-05 [Notice] (Alsa) No chunk received for 5000ms. Closing ALSA.*

I have done an interesting experiment. I reversed the roles of the two Raspberry pi. The Rpi4 with 2 GB RAM became “master”, the one with 4 GB RAM became “slave”. And I have the same problem but in the other direction. The Rpi4 2GB RAM works perfectly while the Rpi4 4GB RAM has the same problem as the previous experience.

What can I do to fix this?
I had installed a newer version of balena OS (2.85.2+rev3; Supervision version: 12.2.11) but the “master” computer could not recognize my Blue Tooth Tp-Link UB400 dongle.

I hope that the explanation of my problem is clear.
Best regards,

Hi Keng-Waï, sorry for the delayed response. Were you able to figure out this problem? To me it seems like there is some sort of network problem. The log excerpt you shared is a bit limited so this can very well not be the case, but it indicates the “slave” is running out of samples to play which are sent over the network by the “master”. If the master keeps on playing but the slave is not receiving anything then network problems can be the reason. In any case, let us know if you are still experiencing problems an we’ll be glad to help (hopefully with a much quicker turnaround :D)