I bought a Ikea Dirigera hub to handle my Symfonisk controllers which I run alongside ST now.
Works fine and will hopefully give me a Matter/Thread border router when Ikea update too… 
(also solved battery drain issues…)
Sorry to repeat a question. Has anybody got the Ikea Symfonisk to work with Samsung Smartthings? It used to work to control my Sonos system when I bought it but now I cannot get it to work. I have updated the drivers to the individual sonos devices and they can be controlled within the app. But I cannot get the Ikea Symfonisk to do anything. It is discovered by Smartthings as ‘Zigbee Thing’. This gives me the option to ‘+ Add routine’. I select ‘Manually run’ … ‘Control devices’ … I pick a Sonos device … ‘Media playback’ … ‘Play’. Add and icon and save. No errors are reported but after doing that the ‘Zigbee Thing’ says it has No Routines.
Ive never had one working out of the box with SmartThings alone. Got an Ikea hub and it works flawlessly and always has to be fair.
For the price its worth it
I’ve been having problems with connecting this device for a while now - I get exactly the same as you described. It used to work fine, SmartThings would recognise button presses and the knob turn, but now there’s nothing.
I’ve tried multiple installing multiple edge drivers but still no luck. I’d prefer to not have to buy a 2nd hub just to get this working, given every other ikea device seems to work ok with ST.