Video is laggy and audio is very choppy

[PaulusMaximus]

Have you tried this

Proxy Editing

Introduction Proxy editing is the process of creating and using low resolution videos and images in places of the original or optimized (Convert to Edit-friendly) files. This provides the advantage that your computer has less work to do in realtime while editing: decoding, scaling, and effects. This is, quite simply, because there are less pixels to compute. Then, when you are ready to export, it will use the original (or optimized) files for full quality. Performance is optimal when the pre…

and this

Preview Scaling

The Preview Scaling setting may be used to reduce the resolution of video processing when you are using a fair amount of filters, transitions, and track blending. This may help with the performance during the editing process. [image] However, keep in mind that the source video or images must typically be scaled down to the designed preview scale, and that will have a processing cost. See Proxy Editing for the remedy to that. Proxy generates substitute clips at the same resolution as preview sc…