Karel,
You can change your timecode from 24fps to 25fps.
Step 1. Creata a new project DO NOT BRING ANY MEDIA IN.
Step 2. Go to Project Setting go to Master Project Settings change Playback framerate to 25 FPS. Also configure everything else the same as your music video project.
Step 3. Save these settings under presets, name it 25fps config or what ever.
Step 4. Load up your music video session.
Step 5. Go to Project Settings then Presets and load the 25fps config, it will prompt you with a message that says something like do you want to change say yes, accept, apply or what ever and you are done. Your timeline is now 25fps.
I always recommend saving the session you want to change under a different name so you have a backup just in case something gets screwed up. But I promise you if you follow these steps it will work.
Gareth