Recording your audio separately from your video and syncing them up is as easy as clapping your hands.
Using this method will not only give you more flexibility but you will end up with superior audio.
Gear I mentioned in this video …
Rode VMPR VideoMic Pro | http://a.co/8wRDLaX
Zoom H4N Handy Portable Digital Recorder | http://a.co/50QOxqg