Unfortunately , this limits the rate of delay change .
When large video delay changes occur the slow tracking rate of these uncompensated synchronizers can cause the audio video sync to be off for several seconds or minutes until the audio delay catches up with the video delay .
Unfortunately , this limits the rate of delay change and when large video delay changes occur the slow tracking rate of these uncompensated synchronizers can cause the audio video sync to be off for several seconds or minutes until the audio delay catches up with the video delay .