# Red Giant PluralEyes 3.5

## Troubleshooting the Sync

If some clips are not synced during the automatic sync process, there are steps you can take to help them sync. If many clips are failing to synchronize, then use the suggestions listed below and make changes as needed.

### Are your audio files good enough?

Length of files. In general, PluralEyes 3.5 can automatically sync clips that include at least 5–10 seconds of good quality audio content. You may run into problems if you use audio clips that are short, like 3 seconds or less.

Another possible issue is that audio clips which are short in length or have indistinct parts can make it difficult for the synchronization algorithm to find a match. This type of issue usually causes a small percentage of clips in a project to be unsynchronized. You can fix them with our touchup sync methods.

Level Audio. If the first sync doesn’t work, try turning on Sync> Level Audio, then running the automatic sync process again. Level Audio is helpful when audio clips have very different levels of softness/loudness, as it can make their sound levels more similar. NOTE: We suggest that you use Level Audio only AFTER the clips fail during the first sync.

Check the files. Check whether the audio is of sufficient quality. PluralEyes 3.5 synchronizes clips by comparing their audio content only. PluralEyes cannot synchronize silent video, and does not use any clappers or timecode that might be present. You can try cleaning up the audio files in an external application, like Adobe Audition, and then reimporting them into PluralEyes.

### Make sure the clips match

First, check whether synchronization is actually possible. If there were periods of time in which only one device was recording, it is normal for the clips from that device to not automatically sync.

Sometimes clips don’t sync because they are, in fact, not recordings of the same event, or they are recordings of different takes. It’s possible that you can sync the clips by hand, even approximately.

### Delete the discontinuous clips

Discontinuous clips are clips that are sequential but have some lost or dropped sound between them. This means the total time of the audio doesn't fully match up to the clips’ length.

In order for PluralEyes to sync successfully, each clip must correspond to one continuous stretch of recording. That sound gap is going to confuse PluralEyes. However, PluralEyes doesn't trim or edit your clips; it just syncs what is there. For details, see Preparing Files for the Sync.

We normally don’t suggest editing your clips before using PluralEyes. However, in this case, you need to fix the problem by removing that sound gap. In your editing application, trim the discontinuous clips so all of the clips are continuous, and then add those clips back into their PluralEyes bins. Then click the Synchronize button in the toolbar again.

### Organize the bins correctly

Make sure each camera bin contains clips from only one camera, and that each audio bin contains clips from only one audio recorder. If the clips aren’t separated this way, the automatic synchronization algorithm will not be able to put them into place.

If clips are not organized correctly into bins, do the following:

1. Delete clips from existing bins so that each bin contains clips from only one device.
2. Add new media bins and import those clips into the new bins.
3. Click the Synchronize button in the toolbar.

### Check settings for ordering clips

If you are not using the Allow sync to determine order synchronization setting, the clips in each bin must be in the correct order before you start synchronization.

Play through some clips in each bin to check that the order is correct. If needed, change the clip ordering method or, if you are using the Custom order setting, manually reorder clips by dragging and dropping them. Then click the Synchronize button in the toolbar to restart the automatic synchronization process.

### Use slower but more powerful algorithms

PluralEyes 3.5 has more powerful sets of algorithms that can improve your sync results. Level Audio helps with clips that have very different audio volumes; it is turned off by default. Try Really Hard tells PluralEyes to do a lot of extra processing during synchronization, and is turned on by default.

Both options often resolve difficult sync situations but they require extra time for processing. Learn more in Choosing the Sync Settings.