Please help with sample play patch

Hi, I have made this patch and the basic goal is to randomly play the samples forwards and backwards and different speeds randomly, it is supposed to be an indeterminacy patch but i can’t figure out why the samples play sometimes and dont play the rest of the time. At the moment i just need it to make some sound, can anyone please tell me how I am being stupid?

Thank you very much, as I said before I am very new to max!!!