GTASnP.com has recently upgraded it's fix for too much game time freezing the camera during unique stunt jumps, among other issues. If you tried the beta and had problems then try again. It should work much better for you.
But there's an unaltered timer related to the last time a mission has ended and I'm not sure if I should recommend an upgrade. In San Andreas a similar value is used to prevent phone calls from ringing for 20 seconds or so after the end of the mission. Is there a similar mechanic in Vice City or can this timer be ignored?
It shouldn't be a serious issue as ending any mission should update the timer, but even if it is a minor issue it should be repaired if the glitch can be identified. Problem is, I don't have Vice City and can't run my own tests.
So the question is, can anyone think of something that might be delays for a short period after the end of a mission? If I know what to look for I might be able to find it in the scripts, but if you've got something pending in your save, please run the timer fix from SnP and see if a problem can be introduced that can be fixed by toggling a mission.
Update: An answer to this question was provided in another topic:
The game timer when a mission is passed is only used to affect Tommy's mood. For up to three minutes after the you pass a mission, Tommy's mood changes to "wisecracking" and he will have a different set of dialogue. Try punching/shooting/carjacking a few peds before and after you pass a mission and you will notice the way he says his lines are different from each other.
Bonus fact: When your wanted level is two or three, Tommy's mood is "pissed off". When it's four or above, Tommy's mood is "angry". They also have different sets of dialogue.