Grundig TK20 old tape recorders recording issue

Hi folks,
Don't know if you can help me with an old tk20  at all. 
For its age, the audio sounds quite okay, but if you want to record anything. Well, soon as you depress the record button (top right of three buttons) there is a loud buzz followed by ALL fuses blowing, showing there is a serious short somewhere.
All components inside look fine after this, and there's no scorching of anything inside at all.
Shame really. Used to do a good job once upon a time. Any clues at all?.