I have set my incoming ring tone to 'tinker' on my N97.
However, from time to time when I receive a call the phone used the default Nokia tune (so hateful!).
I am on firmware 20.0.019 as I cannot upgrade to the latest version yet in my region

It has done this on all previous versions though. I have no change the video ringtone to 'tinker' in case it was picking the wrong tone that way but it did not help.

Anyone else with N97 experience the same issue?

No one with an N97 experienced this then?

yes it is a common fault with the N97

there is just no solution to it.