Hi everyone, new pilot here so please be gentle! Love my Spark, but I would like to find an easy way to take the audio from the cached 720P video that is sent to my phone, and I would like to add it to the 1080P video. There must be some easy way to do that without expensive editing software, just need that one function and I'd be happy. I've searched the archives best that I could, but can't find what I'm looking for. I'm sure it's been covered before so if you could point me to a link, that would be great. Thanks for any help.

DaVinci Resolve can do it... and it's free.

https://www.blackmagicdesign.com/products/davinciresolve

A free download video converter (ask google) can do the job for you. convert the cache video to mp3.

I'm pretty sure you can't add audio to the video from the SD card without an editing program. It doesn't have to be a big, expensive editor. It's one of the most basic functions in editing so any editing program ought to be able to do it (Windows Movie Maker, for instance). But first, you would still have to extract the audio from the streamed video.

Another thread on this: https://forum.dji.com/thread-100090-1-1.html

Get a audio converter do extract the audio  from the 720p video
Load your 1080p video into windows movie maker and add the audio to it

Hi, thanks for the inquiry. The audio can be added, however, the audio that will be produced is due to the mic of your phone on the aircraft. You could possibly add audio via using the third party editing software. Hope you'll get the best recommendation from one of our customers, for you to add an audio to your video. Thank you for the support.