Felix_h97

So my fox doesnt have the usual aux port, but i've managed to put a cable in to the back of the radio which coverts mp3 to cd then play music through cd button. Works a treat. Next step is to try and upgrade speakers. Has anyone done this?/ shed some light? I also have an issue with the front right speaker where a lot of the deeper sounds dont come through, then suddenly it'll work for a moment and then go. I assume this is a loose wire but is there an easy way to get at the speaker and take a look? Thanks Felix.