Core app - pause/play problem

I am a proud owner of the Core for a week now and am getting used to the app used for playing back flac files. I've come across a niggling problem with the Pause/Play icon/buttons: pause works OK but when I pause something and press the corresponding toggled play icon, either nothing happens to the sound or it plays from the next track. The app updates the current display of the playback progress in the app, but nothing happens to the sound other than sometimes playing from the next track's beginning.

Anybody else with this problem? I regard this as quite a shortcoming of the app.

(BTW, I am happy  with the sound quality - I'm using the Naim DAC, an ATC SIA2-150 amp and Quad ESL 61 speakers)