HI to who can help!!
Are the audio file and the video file somehow related in your database? If so, how are you loading them into the repeating groups?
If each repeating group has the same number of files, so you can see that the audio file for video file item # 5 is also 5 because they are both the 5th entry in their respective RG, then you can target the RG item number.
If there is no link between the audio file and the video file, is the goal to just play random audio files with random video files, or are you trying to actually play an audio file that is somehow ‘connected’ or ‘linked’ to a video file?