Firmware Upgrade 4.2.9326.27

Bug Fixed:

  1. Fixed, ADC expansion on Up2stream pro V3 vol- button invalid, stand by button invalid.
    (Up2stream Pro V3)
  2. Fixed, SPDIF IN configuration on Up2stream Pro V3 invalid. (Up2stream Pro V3)
  3. Fixed, Optimize the power-up sequence to fix the power on invalid. (Up2stream Amp Sub)


  1. OLED screen will goes off after 10 seconds without any operation.(S50 Pro +)
  2. Add a SPDIF IN prompt on the OLED when there is no SPDIF IN detected.(S50 Pro +)

4.2.9326.27 only for S50 Pro +, Up2stream Pro V3 and Up2stream Amp Sub currently.


Hello, I have the model S50 Pro, but I do not have this latest update, I want to know where I can get this upgrade

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Hi Chronix, thanks for the interesting for our firmware release. The version 27 is currently only available for PROV3 and AMP SUB only, as we’ve recieved critical bugs in it, so we pushed the update. And you can see we’ve marked the changes with device model.
For other devices, we’ll keep working on it and will prepare the update while changes accumulated.

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I am very grateful for your attention, and your response, I just wanted to know if there is any update for the S50 Pro model and where to get them, I can not find the item here.

Hi @Chronix The newest firmware of S50 Pro is 4.2.9326.26

You can check if your have the newest one or not and let us know!

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Joy, I don’t get that update for my S50 Pro yet, can someone provide me with that update?

Hi Joy…
in my S50 Pro Is showed 4.2.9326.5 p
It’s correct.?
I’ve tried to delete and reinstall 4Stream Google Play but nothing change.

Here attacched screenshot.

The s50 pro is based on an old platform and should be stable enough, and we normally only handle reported bugs. Currently this version is the latest and we supposed it is working well.
We’ll mark the model in the post later to make it more clear.

Woke up this morning to find my Arylic S50 Pro+ had a very dim screen and I had to reconfigure everything including renaming the device. The screen is still very dim and the Upgrade is 4.2.9326.27. Should this have happened and am I the only one?

Hi, we made this change to extend the age of the OLED screen. Now it will have larger brightness when user have operation, and will dimm to lower brightness when no actions in 10 seconds.

Hi there. Just starting direct, because i think i found a little bug.

I tested spotify client on oneplus 5t hooked up on wifi, up2stream v3 pro has direct access to internet over LAN port.

Starting with the internal arylic spotify mode in the up2stream pro v3 i had low noise scratches in SPDIF out, then i switched to Bluetooth input and they were gone!

In bluetooth mode i had some short drops in music playback, but much better sound without the little scratches.

then i switched back to internal spotify client from device and then the sound was ok. testing now 20+ tracks without any problems??

Optical device receiving sound is a sabaj A3.

Support is on one side very fast, but some things are still disturbing.

  • Volume buttons for use in car are to small and disappaering after a few seconds (car mode in app with BIG vol+ and vol - buttons always visible?)
  • manual has still the old reset button infos ( got scared 1 hour, thought i killed it)
  • No information on bitrate in internal spotify streaming mode ( asked on different locations about it, no answer)


I found that version had improved the sound and staging of Spotify (Wifi) alot… Great work. The source is fed to a Topping DX7Pro DAC via Optical and I am telling you, the sound is so much sweeter now…

I have the S50pro+ with Firmware 4.2.8826.24. There is no update in 4tream. How can I get the latest firmware?

Even i am looking for latest firmware.