I can not hear my music once its recorded

I am using audacity 2.0.3 on windows 8 and i have a usb cassette converter that i use. i put my tape in let it play while i am recording and once its recorded i can go back to the beginning of the songs put there is no sound and when i export to itunes or to windows media player there is no sound there either, what can i do to fix this? i am following instructions step by step that came with the book.

see this FAQ from the manual: http://manual.audacityteam.org/o/man/faq_playback.html#usb