Foreword
There seems to be a universal problem with the N97 reverting back to the, annoying, Nokia default ring tone under certain circumstances, after a reboot for instance or with certain contacts.
I believe that this is because of a �time-out� in the software meaning that if a user�s ring tone/contact photo is not loaded quick enough when a call is received it will automatically default to the Nokia tone.
This is something that Nokia need to address in future firmware upgrades.
What follows, works for me:-
The ring tone
Whilst it�s useful to be able to select a track from your music library as a ringtone it does increase the chances of the time-out if it has to look for and load a 4 minute track hidden in the depths of your music library.
Therefore, it pays to trim it down to about 30 sec�s (see fig.1) and, at the same time, I convert it to .aac format, the same as the Nokia ring tones (see fig.2). You can use any audio editing programme for this. I use the free Format Factory one available here:-
Installation
As I mentioned before, it only adds extra time if the tone is stashed away in the deep, dark depths of you Music Library on, say, a Memory card (F: drive). Therefore, I use Y-Browser (available from the Ovi Store �1)
http://store.ovi.com/content/23372
to copy/paste from my desktop to C: and not placing it in any folders. See �Wallander ringtone fig.3.
Once in place I open my tone and select Options > Use tone > and either Assign to contact or Set as ringing tone. I then go back to the tone using Y-Browser and, because I do not want it appearing in my Gallery, I use Options > File > Attributes > and select �Yes� to Hidden (I use this method to hide my message tone and any photo�s/files I do not want my phone to display). See fig.4.
Contact Photo�s
Contact photo�s are another thing I have found that will lead to the phone defaulting to the Nokia ringtone. That is not to say that you cannot use them but in some cases they will need to be edited.
If, like me, you take head and shoulder shots on your N97, to use as Contact photo�s, there is a chance that you did so using the full 5 mega pixel setting. This, it would appear, is too large to load in the default time-out on an incoming call and will cause the phone to use the default ringtone. 640*480 is the optimum size I believe.
I therefore, have gone through my Contact photo�s in Gallery and using the built-in editor, Gallery > select photo > Options > Edit > Options > Add effect > Crop > Manual > crop the photo to reduce size. This can usually be done fairly painlessly by losing some of the background and concentrating on the face.
You can then either choose to replace you Gallery photo with the cropped version or save it with a different name. You then assign this new cropped version to your contact.
Of course, the easiest thing to do would be to take all your would-be contact photo�s using the Basic, or MMS, setting on your camera.
I know that the above is a lot of work but until Nokia can resolve the default ring tone problem this is the only workaround for me.