You most likely have your access control setting incorrect. Take a look at this section on whitelisting: PhoneGap Build Documentation
You might also need to look at CSP (Content Security Policy) - Web security | MDN as well.
Often when external resources stop working, it is one or both these issues.
Thanks for your reply Chris.
I messed around with the white listing setting a lot last night. However this did not solved my issue.
With fresh eye's this morning, i began to wonder if the framework (Phonon) i am using, could be to blame.
I turns out that the framework fired it's function before the href, where my function was called.
What a difference a few hours of sleep make ;-)