Threading Audio/UI with thumbnail Class

I’m trying to produce an audio thumbnail. At first I thought I’d start with a class called AudioThumnailComp that inherits all that it needs…Then I realised I have a Fileplayer class, which loads a file into a class and I also have a FileplayerGUI which paints things to the screen and takes button presses and sends it to Fileplayer to carry out processes there…I wondered if it was then more appropriate to have just Fileplayer inherit the member functions required for an audio thumbnail and then fileplayer gui can somehow repaint this…? is it thread safe or appropriate to split the audiothumbnail objects up like this? It is a case of experimentation, or are there things i need to know to think about this design?08