I have an Up2Stream mini and an Up2Stream Amp v4.
Whenever I group the 2 together, with the mini as the master, then the mini will go full volume, even if it’s set to minimum. The volume sliders have no real effect, unless I slide it to zero, and the sound stops.
The amp V4 works fine, with the group and individual unit volume slider working as expected.
If I ungroup them, then each volume slider works as expected.
In my case I grouped 2x Up2Stream Mini with a S10, the S10 being the Master.
What happened was that the volume on the Mini’s started moving up to max volume, without me getting any control. When I tried to manually slide them back, it started going up to max volume again.
I also had a device connected to the AUX IN of the S10, when I disconnected that device form the AUX IN, the problem was over.
I guess Simon might connected an external DAC for the MINI board, if so, the volume would behave just like this. It’s a known hardware failure for Mini V3, we’ve fixed it in next batch boards, it’s labeled as mini v4 on silkprint, although the SKU of item is still V3.
The issue is the I2S output volume of master device is always max, and if that affects, please request for a exchange, it would be OK. But I’m not sure if the warehouse could distinguish them… please remind for MINI V4 while you contacting.