Delete your media cache. Go to Edit > Preferences > Media Cache and hit Delete . Then restart Premiere. It will rebuild fresh indices. 3. "File Has an Unsupported Compression Type" Sometimes Premiere refuses to index a VFR (Variable Frame Rate) file — typically screen recordings from OBS, Zoom, or iPhones. No index means no smooth scrubbing.

Convert your footage to an edit-friendly codec like ProRes or DNxHD before importing. Indexing ProRes takes seconds. 2. Choppy Playback on Seemingly Simple Clips This happens when the video index ( .cfa ) is out of sync with the actual file. Maybe you renamed a clip outside of Premiere, or the file became slightly corrupted.

If you’ve ever been deep into a Premiere Pro project and suddenly experienced choppy playback, frozen frames, or the dreaded "audio buzzing but video lagging" scenario, you’ve likely encountered a corrupted or missing index file .

✅ Don't let indices clog your C: drive. Move the cache folder to a fast scratch disk.

Most editors ignore indices until something breaks. But understanding what they are can save you hours of frustration. In simple terms, an index is a temporary cache file (usually with a .cfa or .pek extension) that Premiere Pro creates to read your media faster.

Have a Premiere Pro indexing horror story? Drop it in the comments.