[SOLVED] Choppy sound using Bluetooth (Zero 2 W)

[citro]

Some more experimentation.

I bought an Orico bta-508 v5.0 UBS Bluetooth dongle - based on RTL8761B chip.

I booted a fresh install os Raspberry OS 64bit lite and disabled the integrated bluetooth:

Code:

sudo nano /boot/config

and added the dtoverlay=disable-bt line


Reboot, than I attached the dongle to RPi using a Micro USB Male to USB Female OTG Adapter / cable.

The fresh RaspOP install had no BT drivers, but the problem was solved with

Code:

sudo apt update && sudo apt upgrade -y

I added the pulseaudio and mpg123 packages, paired / connected the speaker, mounted the MP3 share from NAS, mpg123 something.mp3 and.... clear sound. Well, not 100%, but perfectly usable.

Next step: fresh MoodeAudio install (8.2.4, 64bit).
I disabled internal BT (dtoverlay=disable-bt). After reboot, I connected the USB dongle - it was recognized properly.

I tried connecting the speaker from Moode web interface, but I was only able to pair it.

I SSH-ed the unit, and tried to manually connect the speaker using bluetoothctl. I could not do it.


/var/log/syslog shows a2dp-sink profile connect failed / a2dp-source profile connect failed errors.

The only solution I found was to

Code:

sudo apt install pulseaudio-module-bluetooth

After that, I was able to connect the speaker. I only tested radio stations, there is sound output, but is unusable (worse than when using internal BT).

[TheOldPresbyope]

@citro

Sorry you're having these problems. My experience has been different.

Just now, I grabbed an ASUS USB-BT400 USB 2.0 Bluetooth 4.0 Adapter out of my parts box and plugged it into an RPi Zero 2 W using a micro-USB-to-USB cable. Booted moOde 8.2.4. This player connects to my LAN via the Zero 2 W's internal WiFi transceiver and my WiFi Access point.

- disabled the internal BT adapter in the moOde System config panel and rebooted.
- enabled the Bluetooth Controller in the moOde Renderers panel
- placed my JBL Flip 2 Bluetooth speaker in pairing mode
- in the moOde Bluetooth Control panel submitted "SCAN (Standard)"
- selected "JBL Flip 2" from the list returned by the scan and paired with it
- connected to the JBL Flip 2
- changed Audio Output to "Bluetooth Speaker"

I'm listening to station "Soma  FM - Drone Zone" via the JBL speaker without noticeable artifacts. (The nature of the musical programming on this station makes it easy to hear dropouts/interruptions.)

Regards,
Kent

[citro]

Thank you, Kent.
I followed you guide, and I was able to connect the speaker. The only difference: I had to submitt "SCAN (Plus LE devices)".

However, the sound quality is bad (there is hardly any sound). It does not matter if I'm streaming Internet Radio or I'm playing the local "Stereo Test - Koz LR Channel And Phase".

I will experiment some more

[Tim Curtis]

This thread should prolly be closed since is > 6 months old and no solution or repro including from Pi dev https://github.com/RPi-Distro/firmware-nonfree/issues.

OP's best bet is to try a different Pi or continue the discussion on the Raspberry Pi Forums.

[citro]

@Tim Curtis: what does "repro" mean?

[Nutul]

@Tim Curtis: what does "repro" mean?

repro => reproduce

[citro]

It looks like the issue is solved - I updated NVRAM settings, as advised on github.

According Raspberry engineers, the solution has the downside of significant reduction in WiFi throughput, but for Moode it might not matter.

Currently I'm streaming Internet Radio over BT to a speaker 2 rooms away (2 brick walls, 6-7 meters).

[Nutul]

It looks like the issue is solved - I updated NVRAM settings, as advised on github.

According Raspberry engineers, the solution has the downside of significant reduction in WiFi throughput, but for Moode it might not matter.

Currently I'm streaming Internet Radio over BT to a speaker 2 rooms away (2 brick walls, 6-7 meters).

In the end it was the same old story: interference between wi-fi and BT...
Glad to hear you were able to solve it, and in a relatively easy way.

Cheers.

[TheOldPresbyope]

And now the rest of the story. 

Based on this thread and a PM from @citro, I looked at the firmware files for the RaspiOS release on which moOde 8.2.4 is built. Surprise! The relevant firmware file for very model Pi containing the Cyprus combined WiFi/BT transceiver [1] EXCEPT the Pi Zero 2 W contains this "fix" already. You can see for yourself in /lib/firmware/brcmfmac* files.

One can only wonder why the Zero 2 W was left behind. [idle speculation}Maybe wishful thinking that Cyprus had solved the problem with its latest chips? [/idle speculation]

Regards,
Kent

Specifically, the Pi Zero W, 3A+, 3B, 3B+, 4B, 4B CM, and Pi 400.

[TheOldPresbyope]

As an aside, I think it's misleading to see this as a WiFi-BT interference issue per se. Certainly, these can occur under the right conditions but a number of us moOde users have already demonstrated that we can run various combinations of separate WiFI and BT transceivers side-by-side without interference to audio service. 

The issue being addressed here specifically arises in the combined transceiver chip and firmware that Cyprus provides to the RPF.

Just my 2-cents worth.

Regards,
Kent