JBL SA750 losing connection at random intervals

Roon Core Machine

Windows 10
Gigabyte X570 Aorus
AMD Ryzen 9 3950X

Networking Gear & Setup Details

ASUS RT-AC88U with latest Merlin firmware and multicast routing enabled. WIFI disabled on the ASUS RT-AC88U instead I run two Unifi UAP-AC-Pro for WIFI.

Roon Core is connected to Ethernet.
The JBL SA750 is running on WIFI.

Connected Audio Devices

JBL SA750 connected to WIFI

Number of Tracks in Library

2232 Tracks, mainly from Tidal.

Description of Issue

When playing music on the JBL SA750 it will occasionally suddenly stutter and then the Roon Core loses connection to it. Shortly after it will pick up the connection again and I can continue playing music. It happened at 10:23 AM, but also at 7:43 AM (see log link below).

I suspect it might be a network problem, but I feel like I have tried everything related to the WIFI setup in the Unifi controller. I have not yet tried connecting the JBL via Ethernet, this is my next step. But figured I’d let it run on WIFI so there was a chance of debugging the problem.
I’ve also tried factory resetting the JBL, updated to the latest firmware and then factory reset (per the JBL firmware update instructions).

Logs from Roon and the JBL SA750 can be found here Roon logs - Google Drive

Please note that the JBL log only contains information for the 7:43 AM connection drop.

Had a few more dropouts, but the latest stopped the WIFI on the JBL SA750 from working until I shut it down and started it again. That’s happened once before, but I didn’t have a log for it then.

I also tried removing automatic shutdown from the amp to see if it would lose WIFI if nothing was being played on it. I left it running for around 16 hours without a single drop, so it seems I must be at least playing something for it to lose connection.

Here’s a pastebin of the latest roon log (just the part where it fails)

Next up I will try bypassing Roon and stream directly through Tidal.

@Soren_Ollgaard, based on what you are experiencing the issue does seem to be related to your network. Your Ubiquiti screenshot of the SA750 WiFi information shows that what the SA750 is receiving, 6.30 Mbps, is low especially in relation to what the SA750 is transmitting. While Ubiquiti is noting that you have a good WiFi Experience, Roon requires a strong WiFi signal (if WiFi is used) for connecting to endpoints. 6.30 Mbps may be too weak for a consistent connection; even though the SA750 may not be using or needing 6.3 Mbps, the low speed may be indicative of a poor connection.

Is there any way to change what AP the SA750 is using? Or connect the SA750 with an Ethernet cable? This way the problem may be localized to a network issue.

UniFi is is reporting bad client ap balance. Do you have any of the bandwith limits set on the Wi-Fi network? As it looks like it’s limiting it or the device has a fault Wi-Fi receiver. What is you ap power settings for 5ghz. Do you have Wi-Fi QoS set perhaps?

Post here on UniFi forum about issues with this problem


You might get slightly better performance via Tidal as it streams flac directly which is less bandwidth, Roon decodes all files to PCM to send to endpoints and these are larger files as a result as they have no compression.

@Robert_F @Simon_Arnold3 I believe the bad client AP balance reported was just because nothing was playing at that time. While playing music Rx and Tx were nearly identical at around 160-170 Mbps. But it could just be a coincidence, it’s possible that something could be interfering with the signal strength as well. I’ll investigate a bit more on that part.

I’ve just received a Unifi Dream Router that I will try with WIFI before going the Ethernet route. I’ll report back my findings once I have some conclusive testing done.

Thanks for getting back to me!

After creating a separate WIFI network for the amp and forcing that network to only to use 5GHz it seems to have stabilized. I noticed that if 2.4GHz was enabled it would sometimes switch to that network even if the connection was good. I was able to play music on it for 13 hours straight without any dropouts. I’ve unfortunately been unable to do more testing than that one session due to work, but at least it’s improved and I’d almost consider it solved.

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Glad to hear some progress on your stability issue. Keep up posted, if the system remains stable we can mark this as solved.

I’ve finally been able to test again, and I’m sorry to say that unfortunately the problem still persists. I will try with Ethernet now, even though I find it hard to believe that the wifi is the issue. Looking at the connection quality and how much data is transferred from Roon there should be no problems.
It will be a huge pain to get a cabled connection, but I’ll give it a shot.
I gotta say, I believe the JBL SA750 just have bad software, and maybe the “Roon ready” label was premature. I’ve been reading that the Arcam SA30 have been giving people issues as well with buggy software, and afaik the SA750 is mostly the same hardware/software.

Not a happy camper :disappointed:

Mabey this clears things .

It doesn’t. First of all, the stuttering that happens before it drops the connection does not happen if I manually kill the connection. If I manually kill the connection the music just stops without any stuttering. This leads me to believe that something crashes in the amp. Hence the belief that it’s a software issue.
Additionally I’ve been streaming far more data intensive things on the same wifi in the same location without any issues for many hours.
My previous success that lead me to believe it was fixed seems to just be a fluke.

I’ve now got Ethernet connected to the amp and will test for a couple of weeks. Additionally I’ll contact the dealer where I bought the amp and ask them about borrowing another Roon Ready device and try to run that device via wifi, just to try and eliminate wifi as being the issue, even if I don’t have any problems with the Ethernet connection.

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I can now say for sure that the problem has nothing to do with bad wifi. I just had it happen while the amp was connected via Ethernet.
Now I’m really unsure how to proceed. Wondering if I should return the amp?

Probably contact JBL and see if there is something wrong with the amp.

After speaking with both the dealer and JBL and getting nowhere, I remembered that occasionally, although extremely rarely, Roon would stop playing when listening through my USB DAC as well. So I tried installing Roon server directly on my Synology 1817, even if it doesn’t exactly meet the desired specs.
Since doing that I haven’t had a single dropout on my JBL amp, nor on my desktop for that matter, but desktop would take a very long time to test since it was so rare. It could just be a fluke and it might still happen on the JBL amp.

I wonder if it could have something to do with my custom AMD Ryzen power plan (Balanced LowPower 10-v11). I remember when I had success for 13 hours straight, the computer was busy rendering some stuff out which would have prevented it from going into low power mode. This is complete speculation of course, and to test it I would need to install Roon server on my desktop again.

Again, it all might just be a fluke, but I have listened for a combined 15-20 hours without any issues. Will give it another couple of weeks before I am completely confident that I’ve found the culprit. And then I’ll be tempted to take a deeper look at the power plan.

As a sidenote, I noticed that when the amp would stutter and stop playing, while being connected via Ethernet, it would still be connected to the network. Only when using wifi it would lose connection as well. So whatever caused(causes?) the issue, was not a network issue, but maybe some sort of bad data from the server that would cause the crash, and the wifi connection dying just made it look like a network issue.

Lots of speculation here, but just putting it all out in case someone else has experienced something similar.

So… after changing my server to my Synology I didn’t experience any dropouts since my last post. Until I did! Except, this time I wasn’t using Roon. So it turns out the problem is with the amp itself and not Roon.

Turns out the JBL SA750 is pretty buggy.

You are welcome to close the thread.

Thanks @Soren_Ollgaard. I marked this as solved and will close it.