I can’t manage to make training work… please help me out

I m a newbie when it comes to deep learning, but I am trying to use a code from git and train the network on my own data. however, it takes forever..it took 80 minutes for 1 epoch, and the number of epoches is 1000. i also tried reducing batch size and using google collab.. please,i dont get what i am doing wrong… at first i tried running on cpu,then on gpu,but i get OOM error even when changing parameters.. any help is appreciated. This is the code : https://github.com/markusaksli/ai-music