RS520: MCU update loop after [Early Access] v5.12.04

Early Access
#1

After the latest update to version [Early Access] Ver 5.12.04, a window pops up prompting me to update the MCU to a new version. After clicking the Yes button, the device reboots, and once it boots up, the MCU update window appears again — and this repeats endlessly, meaning the update gets stuck in a loop. As a result, I’m unable to update the audio device’s components.

For now, I’ve rolled back to the stable version 5.9.0.9. But as far as I understand from reading the forum, this means I’m now unable to update the MCU on my device at all.

I also noticed that after the update, the ROSE ID in Rose Connect One was displayed as ‘ABCD’. However, after rolling back to the stable version, it started displaying correctly again.

This is completely unacceptable for a premium device at this price point!!!

1 Like
[Early Access] Ver 5.12.05 - SW Update Notice
#2

@Geka4epist
Thank you very much for the detailed description of the issue.
As we are currently unable to replicate this issue on our end, we plan to run repeated tests across multiple devices to analyze and identify the root cause.

In the meantime, we would like to ask a quick clarifying question regarding the issue: When the MCU update pop-up appeared and you selected “Yes,” did the device reboot after the progress bar finished, or did it restart immediately without showing the progress bar at all?

Could you please check if you have any prior history of MCU updates?

Thank you for your cooperation.

#3

Thank you for your response.
To answer your question: after I click the Yes button, no progress bar appears at all — the device reboots immediately.
As for the MCU update history: before this, I had never received any MCU update prompts on my device at all. This was the first time the MCU update pop-up ever appeared.

I’d also like to point out that this issue looks very similar to a previously reported case on the RS151: RS151 - Repeated Audio MCU Update message. In that thread, the same endless MCU update loop was reported back in October 2025. It seems the same class of bug has now appeared on the RS520 with the [Early Access] v5.12.04 update.

One more thing I’d like to add: my RS520 occasionally fails to wake up from standby. Sometimes it doesn’t respond to either the remote control or the power button on the unit itself — I can hear the power relays clicking when I press the button, but the device doesn’t actually turn on. It can take quite a while (and several attempts) before it finally boots up. If the MCU update is meant to address issues like this, then the broken update process is preventing me from receiving a fix for a real, recurring problem with my device.

I hope this helps your team connect the two cases and identify the root cause, and that the fix can be delivered via a software update.

#4

Regarding your comment "This is completely unacceptable for a premium device at this price point!!!

  • Take note you updated an “early access” update ← this is not an official release. Early Access updates are for users willing to accept bugs and willing to do beta testing (especially for the new features).
2 Likes
#5

Fair point, and I fully accept that Early Access builds are beta — I knew that going in.

But my concern isn’t a buggy new feature, which is expected in beta. It’s that the MCU update process itself appears unsafe: it enters an endless reboot loop, and a very similar issue on the RS151 reportedly required a dealer-level firmware reinstall to fix. A broken feature is fine in beta; an update mechanism that can potentially leave a device unrecoverable is a different category of problem.

I also have a separate issue that exists on the stable firmware too, so it’s unrelated to Early Access: my RS520 occasionally fails to wake from standby. It doesn’t respond to the remote or the power button — I can hear the relays clicking, but the unit doesn’t turn on, and it takes several attempts to finally boot. Ironically, this is the kind of thing an MCU update might fix — which is exactly why being unable to update the MCU concerns me.

And on the price point: my issue was never that a premium device must be bug-free. The reasonable expectation at this level isn’t perfection — it’s that the fundamentals are solid: that an update can’t soft-brick the unit, that there’s a safe rollback path, and that issues get addressed when reported.

That’s all I’m asking for — and reporting it is exactly what Early Access feedback is for.

2 Likes
#6

@Geka4epist
Thank you for the detailed explanation. For further review, could you please provide the system version info from Settings > System Information, as well as the MCU version info from the Detail view?

#7

Hi there,
Here is the complete device information from the Device Version panel:

  • Device Version: 5.9
  • Rose OS: 5.9.09
  • Rose Ware: 5.9.07.1
  • Rose Service: 5.9.07.1
  • Rose Queue: 5.9.07.4
  • Rose Old Radio: 5.9.07.3
  • Rose Radio: 5.9.07.3
  • Rose DualService: 5.10.01.7
  • Rose Equalizer: 5.10.01.1
  • Rose FileManager: 5.9.07.2
  • Rose SmbService: 5.10.01.1
  • Rose SyncService: 5.10.01.1
  • Rose VUMeter: 5.10.01.1
  • SDK: eng.rose.20250922.140034
  • Kernel: 4.4.83
  • MCU: 1.2.38
  • eARC: 20.22.8.10
  • XMOS 3147

As mentioned in my earlier posts, I’m currently on the stable build, having rolled back from [Early Access] v5.12.04.

#8

@Geka4epist
Thank you for confirming. Please also provide the ROSE ID from your device’s Settings > System Info.

#9

Hi, I’ve sent my ID by PM.

#10

Hello @Geka4epist ,

Would you check the personal message I sent you?

Best Regards,

#11

Hi, I’ve replied to you by PM

#12

Hello @ROSELOA

I installed the new EA 5.12.05 to test whether it resolves the MCU issue. Here is my feedback:

What improved: The ROSE ID now displays correctly, and the MCU version is read properly — the update popup offered to update from my current MCU 1.2.38 to 1.2.40 (on the broken 5.12.04 it had shown incorrect versions, 1.0.18 → 1.0.22). So the ROSE ID fix did correct the version-reading problem.

What is still broken: The MCU update itself still does not install. When I tap OK to update, the device reboots instantly with no progress bar, and the MCU version remains unchanged (still 1.2.38). The popup keeps reappearing, so the update loop is effectively back — the MCU simply cannot be updated.

One additional issue I noticed in 5.12.05: the new Symphony Premium app shows its icon on the home screen even though it is not actually installed (RoseStore still lists it as ‘not installed’), and the icon cannot be removed — it reappears on the home screen even after I deselect it in the icon settings.

I have now rolled back to the stable firmware (5.9.0.9).

So while the ROSE ID fix worked, the core problem — the MCU failing to update — remains unresolved. Since this appears to be a software issue affecting multiple users (I’ve seen similar MCU update reports on the RS151 as well), I’d be glad to help test any further fix.

Regarding your offer to inspect the unit, I’m still awaiting your reply to the private message I sent with my questions about the logistics.

Thank you.

#13

Hello, @ROSELOA and @Rose_love

I wanted to share an important finding that may help your team identify the root cause of the MCU update issue.

After rolling back from EA 5.12.05, I updated to the latest official firmware 5.11.01. Once the update completed, the MCU update popup appeared again — and as before, it failed: the device rebooted instantly with no progress bar, and the MCU version remained unchanged.

At that point, I had an idea: I removed the installed Samsung 870 EVO 4TB SSD from the internal slot and rebooted the device. This time, the MCU update completed successfully — from version 1.2.38 to 1.2.40, with a proper progress bar.

This strongly suggests there is a bug in the MCU update process related to the presence of an internal SSD. The update appears to fail when the SSD is installed, but works correctly without it. It is possible that the MCU firmware file is being read from or written to the SSD during the update process, causing a conflict or failure.

I hope this helps your team reproduce and fix the issue. This may also explain why you were unable to replicate it on your end — if your test units did not have an internal SSD installed.

Thank you!

1 Like
#14

@Geka4epist
Thank you for your help with the root cause analysis. We will review this internally to analyze the issue and determine future improvements.

1 Like
#15

@Rose_love
Thank you for the response.

Now that the MCU has been successfully updated, I’d like to understand what my next steps should be.

Could you please clarify whether the issue I experienced (MCU update failing with an internal SSD installed) is likely a software/firmware bug that will be fixed in a future update — or whether it could indicate a hardware issue specific to my unit that would require a warranty service?

This would help me decide whether I need to send the unit back for inspection, or whether I can simply continue using it as normal once the fix is released.

Thank you.

#16

Have you reinstalled the SSD after the to see if it functions as desired?