I would try a very small slideshow only project - e.g. 1 menu, 5 slides. It would help if you have a very small project to test.
I would also build to an image or folder and test with Total Media Theater 5 (just testing 6). Many software players do not emulate slideshows and have problems even when a burned disk does not. If you don't have TMT and create the little project and it shows the problem, you can send to me for test.
The most likely problem is image size or junk in the mp3.
If you get the problem with the small project, replace the images with ones scaled to the exact project size, to confirm that fixes the problem. If it does, it gives you some info.
Convert the mp3 to wav. Try that.