You can try the following methods to solve this problem:

1. Make sure the network connection is stable: Unsmooth song switching may be caused by an unstable network connection. Make sure your Tesla vehicle is connected to a stable network. You can improve connection quality by switching to a stronger network signal or connecting to a reliable Wi-Fi network.

2. Clear cache data: In the QQ Music application in Tesla vehicles, try to clear cache data. This can be done by looking for a "Clear Cache" or similar option in the app settings. Clearing the cache can help optimize application performance and may improve the smoothness of switching between songs.

3. Update the software version: Make sure your Tesla vehicle and QQ Music application are both the latest versions. Updating vehicle software and application versions may fix known issues and improve performance.