I have the latest firmware on the osmo action, using the cynova adapter and the rode videomicro, when plugging the adapter and mic in i get the mic icon on the screen, but it does not light up the levels and the audio on the recording is completelly mute. I have tested the mic on another device and it works, the onboard audio works too,
any other suggestions?

edit:
I have now got hold of a second cynova adapter and the same issue.
is there a way to re-flash the firmware?  is anyone else having this issue?

I had the same problem with audio, I used Cynova adapter and checked everything but nothing.

Troubleshoot:
check the actual rode video micro side,  I know the 3.5mm jack need a firm push, it is    the jack and cable, no space   there .  take a photo,  or do a vid showing.

also take out the frames using, make sure the cynove is in place, aftermarket cases wil lcause issues that foam. mine never been removed, or aftermarket frames used.  contact Conva and they will replace for free. not dji

it seems possibly something is not right with the firmware, as I cannot switch screens while recording either.
going to log a support request to get firmware updated again and see if that helps

action jeff Posted at 8-12 02:04
it seems possibly something is not right with the firmware, as I cannot switch screens while recording either.
going to log a support request to get firmware updated again and see if that helps

let me know if they have that? DJI requested to send the camera in for  dignostics, and firmware  reflash is  not allowed, disabled .  looking forward to that answer. it has been 5 days and no one responded to my email, but answered via chat.

Make sure you are using a TRS not a TRSS mic ??? That's the only thing I can think of.

proven trrs works.

action jeff Posted at 2020-8-12 02:04
it seems possibly something is not right with the firmware, as I cannot switch screens while recording either.
going to log a support request to get firmware updated again and see if that helps

Hello,
I am facing the same issue, no sound just a beep noise,  dji support asked me to courier the unit at their service center which I did and then they asked to courier the cynova adapter too, I couriered both the products and they kept it for almost 35 days...when I checked with them they said unit has been checked and working fine now ..they sent me back the product but when I checked they did not even resolved the issue and sent back the product as it is.  I am totally off with the unprofessional approach.

If you have found out the solution, please let me know. I will be thankful.

Well did they even ask you about the Mic you are using, not mentioned, that can be one reason why the unit worked for them, not you?  so Please this is today. you have youtube you can make a sample and present to all to back up your issue.