I got a response to my contact to them, which basically says "We do not have information on why your transaction may not have been approved... wait 30 minutes... and try again... we are unable to see exactly why the transaction was declined... if your card resulted in ... the codes listed above, that card will be blocked from further billing attempts for 24 hours..." (codes mentioned being 601, 401, 105)

If they want people to subscribe, they need to find a way to figure this out and fix it. How can they seriously think it is acceptable to charge people a monthly fee, but not be able to troubleshoot their payment system?