Ok, I'm having this issue where in Firefox on a desktop and Safari on an iPad the url checkout/onepage redirects to checkout/cart. So from the actual checkout process to the cart again. Even if I manually type in checkout/onepage I just get redirected to the cart again. Magento, PHP, and Apache are not throwing any errors in the entire process or warnings.
Site: www.cepcompression.com Magento Version: 220.127.116.11
Edit: Found out that if I turn off Secure Frontend URLs it works fine but then again I can't turn them off.