| Video does not appear in the queue | The file picker, drag-and-drop action or browser access may not have completed. | Use the Choose files control again, verify the file exists locally, and try a supported file without renaming its extension. |
| Source video fails to decode | The container may contain an unsupported codec, damaged stream or protected media. | Check the original in a trusted player. Try another authorized source or a different conversion environment if decoding still fails. |
| AVI finishes but will not play on an old player | The codec, profile, resolution, frame rate or audio stream exceeds device capabilities. | Check the hardware specification and convert a short sample using a conservative Xvid/DivX plus MP3 preset. |
| Converted AVI is much larger than MP4 | AVI output uses a less efficient codec or uncompressed audio. | Try Xvid instead of MJPEG, lower resolution where acceptable, and adjust quality after reviewing artifacts. |
| Video has no sound | Audio may use an unsupported codec, an absent track, muted settings or failed stream mapping. | Select a compatible audio output such as MP3 where offered, check volume and test sound before processing the batch. |
| Audio drifts out of sync | Timestamp conversion, variable frame rate or speed changes may alter timing. | Retry with standard frame rate and unchanged speed; test a small section with recognizable dialogue. |
| Image looks stretched or squashed | Cropping, pixel aspect ratio or output scaling changed the intended proportions. | Restore the correct aspect ratio, avoid forced width-height combinations and compare the output with the original. |
| Video appears sideways | Rotation metadata or manual transform controls were applied differently during output. | Set rotation deliberately, inspect a sample and reconvert from the original if the result remains wrong. |
| File looks blurry or blocky | Low output resolution or aggressive lossy compression removed detail. | Use more appropriate quality settings and source dimensions; remember previously lost detail cannot be restored. |
| Conversion remains at initial loading | The FFmpeg WebAssembly resources may be loading slowly or a browser extension may interfere. | Keep the page open, check the connection for initial loading and retry in a current supported browser. |
| Conversion stalls midway | High memory use, browser throttling or difficult source decoding may interrupt the job. | Try a shorter file, fewer concurrent jobs and available memory; keep the active tab open. |
| Browser crashes during large AVI export | The output and temporary media buffers may exceed available RAM or browser limits. | Close memory-heavy tabs, process shorter clips, reduce output requirements or use a desktop conversion workflow. |
| ZIP download does not contain every video | Some batch items may have failed or the ZIP creation was interrupted. | Check job status and individual downloads, retry missing files in smaller batches, and validate the ZIP after extraction. |
| Download does not start | Browser download permissions, blocked pop-ups or temporary file creation could interfere. | Check browser download settings, retry from the completed job and make sure adequate disk space remains. |
| The output stops early | A trim range may be set incorrectly or the conversion could have ended prematurely. | Check trim boundaries, retry from the original and compare expected and actual duration. |
| MOV or MKV subtitles have disappeared | AVI output commonly lacks the subtitle handling of the original container. | Preserve the source and use a subtitle-compatible workflow if captions or multiple subtitle streams are needed. |
| MJPEG AVI will not import into an editor | The specific editor may require a particular codec profile, audio encoding or frame layout. | Read the editor format requirements and test a simplified MJPEG/PCM export or its recommended intermediate. |
| The URL source cannot be imported | The address may point to a webpage, have expired access, block cross-origin requests or require authentication. | Use a permitted direct media URL or locally download an authorized file and choose it manually. |
| AVI plays in VLC but not on USB hardware | VLC supports a broader codec range than the embedded decoder in an old TV or player. | Match the hardware-approved codec, bitrate, size and USB file system; verify on the actual device. |
| The video turns black after a few seconds | Source stream corruption or an encoding failure may affect particular timestamps. | Inspect that part of the source, retry without extra filters and test a shorter section to isolate the issue. |