Why won't my ringtone play longer than 5 seconds?

I have ringtones that are greater than 5 seconds in length, why does the passport stop after 5 seconds of a 20 second ringtone?

I'm not able to replicate this issue..as a professional I use a standard ringtone, but I just set one to an mp3 to test this for you amd it played right through, or until voice mail kicked in anyway...