H50 distorted audio when using Bluetooth + Multiroom (Up2Stream Amp V1)

Whole House Products & Projects
1

I am experiencing a problem with my Arylic setup where the H50 outputs heavily distorted audio when Bluetooth is used together with Multiroom.

My setup:

  • Arylic H50
  • Arylic Up2Stream Amp (V1)
  • Phone: Fairphone 5
  • Router: ZTE MC801A
  • Network: both devices connected via Wi-Fi.

The problem:

  • If I play music via Bluetooth directly on the H50, the sound is clean.
  • If I play music via network streaming / 4STREAM, Multiroom works without any issues.
  • However, when I connect my phone via Bluetooth to the H50 and then enable Multiroom with the Up2Stream Amp, the audio output of the H50 becomes heavily distorted immediately, the Up2Stream Amp continues to play clean audio.
  • If I do it the other way around (connect to the Up2Stream Amp via Bluetooth and enter Multiroom then), there is no distortion.

So the distortion only affects the H50 itself when it is the Bluetooth receiver and Multiroom master.

Using Bluetooth from the Up2Stream Amp is not a viable option though, since the Bluetooth range of the Up2Stream Amp is not far enough to cover my whole flat. I want to have the option to use Bluetooth to stream via Youtube or have other people easily play from their phones.

Troubleshooting steps already performed:

Bluetooth / codec

  • Reduced Bluetooth volume
  • Disabled HD Audio on the phone
  • Forced SBC codec instead of aptX
  • Tested both SBC and aptX codecs
  • Repaired the Bluetooth connection after changing codecs

Network

  • Moved the Up2Stream Amp very close to the router (RSSI improved but the issue remained)
  • Verified stable Wi-Fi signal
  • Tested with both devices on the same Wi-Fi band (2.4 GHz)

General

  • Updated firmware on both devices
  • Restarted devices several times
  • Tested different order of operations (Bluetooth first vs Multiroom first)
  • Tested different volume levels (distortion occurs immediately even at low volume)

Observations/Recap

  • Bluetooth playback on the H50 alone works fine.
  • Multiroom playback from network sources also works fine.
  • The distortion only occurs when Bluetooth is used as the source and Multiroom is active for the H50, not for the Up2Stream Amp.

Could this be a known issue with the Bluetooth restreaming pipeline on the H50?
Has anyonecap experienced the same behavior, or is there a firmware update or workaround that fixes this?

I also tried to find similar problems (without any luck) and already contacted the support.

Thanks for your help, any input is appreciated!