I started this project 1/29/19 using exported iphone video w/ attached audio and everything was going okay. Opened the program this morning and it required an update. After updating, my timeline's audio was slower and didn't sync, even though it's in the video clip. I clicked on "Play audio while scrubbing" and it fixed the problem. When editing all of the audio was syncing just fine. When I go to export, the file has the sync issue again. Can anyone help?
If I'm understanding you correctly, you've exported video taken on an iPhone to editing on Rush on a computer. I think this is where the issue is! iPhone videos have a variable frame rate that can confuse editing software. You can convert the iPhone video to a constant rate using https://handbrake.fr/ and then re-import it into Rush and hopefully it will work correctly.