Joomla 2.5.7 - CB 1.8.1 - CB Subs 2.0.2

I have a membership site with 2 simple plans - one free & one paid - and I've set up both PayPal and Off-line payment gateways. Both are set up for single payments only.

If I enable both PayPal and Off-line options, when the user selecting the paid membership gets to "Choose your payment method", when you select an option and click continue, nothing happens.

If only one payment option is enabled, they both work fine.

Is there something I need to change in my setup to allow both options? I've reviewed all of my settings and don't see anything obvious.

I changed the setup from using radio buttons to using image buttons and the issue seems to have resolved.