Fatal error: Allowed memory size

Hi, I had to deactivate the Coursepress plugin because I get this error:
Fatal error: Allowed memory size of 67108864 bytes exhausted (tried to allocate 49152 bytes) in /home/dmocca1/public_html/estheticnet.com/dest/wp-content/plugins/coursepress/includes/unit-modules/audio.php on line 111

What can I do to prevent this to happen?

Thanks!
Damian