Track conversion RF2 Warning message

Hi guy's, i'm in the process to convert an rF1 track to rF2 everything is working fine no CTD in devmod and i solve all the RF2 Warning that i got except from this that i can't seem to figure out. Any idea how to solve the issue ? thanks in advance

 

These are errors from the skip barber car – not from your track

 

thanks for the info

 

To avoid these Error Messages, you can install a small Sound Package, that i did upload a few Months ago.
More Info can be found here:
https://forum.studio-397.com/index.php?threads/missing-sounds-in-moddev.75946/