Adding clips into a video delays the audio track

Hello, so I have this corrupted video where there are intervals in between where the audio and video just cut out. I however have another video but with lower quality and I’m trying to substitute the missing bits with the lower quality video. The problem is when I cut out a section of the original video and replace the section with the lower quality one, the original video audio becomes delayed, does anyone know how I would go with this? Thanks