I have a similar problem with my Medion MD 86562.
I first select to stream to it from PC. Then a long wait and a message about buffering.
Then I go to the Medion device and select ‘Shared media > Stream what you hear > Music > Stream what you hear (mp3)’ the device plays the music for about a second then jumps out of the playback mode.
I return to the PC and see in the SWYH-Menu that the check-mark is no longer set for ‘Stream to > Medion device’
Any clues what might be wrong?