Hi all,
-----------------------------------------------------------------------------------------------
UPDATE: I got the firmware update to work, see next post below for explanation... might help you if you are having the same failed update.  Bottom line; the update failed 100% of the time until I unplugged the Ronin to GH5s USB control cable.  Even though the camera and gimbal were both turned off during the firmware update attempts, as soon as I unplugged the USB side of the cable from the camera, the update completed successfully.

I'll leave the posts below as-is so you can see if this problem is similar to a problem you are having.
-----------------------------------------------------------------------------------------------

I had posted this same info to the Announcement post for Ronin-S Firmware: v 1.4.0.30 on 8-30-18  Strangely, this post is only on the Ronin home page, not the Ronin-S page.

Anyway, I tried updating today and it is a bit of a mess.

Basically, DJI Assistant 2 fails at 81%.  I followed the steps to try again (including booting and shutting down the Ronin, quitting the apps, rebooting the computer, etc)  and noticed that DJI ASS2 says the firmware is updated and only gives me the opportunity to "Refresh".  I tried to Refresh several times and the update only got as far as 61% before it says it failed again.  Now it only makes it to 61% each time.  

The enclosed image shows the errors I got on the first attempt to update. (note that when the error page comes up, it says Update completed at 100%).

The latest version of the Ronin app on the iPhone now says that the Ronin-s Firmware version is "N/A".

Overall, not a great experience, but this is what we have gotten used to with DJI firmware updates.  FWIW: the only thing I can test to see if the gimbal is updated is the shutter release button half -press and quick full press, and they seem to be working with the new functionality.  But I feel like my firmware update is not solid and things might show up down the line.  "NA" firmware version is not satisfying.

FIRMWARE UPDATE SUCCESSFUL...

Ok, here is what I believe was wrong.
The firmware update instructions say to keep the Ronin off, but to add your camera and make sure it is balanced.  Part of the balancing process is to plug the USB cord (from Ronin to my Gh5s).
Although I left the camera turned off during the Firmware update, I believe that the camera being plugged in caused the problems as described above.

After several failed attempts to update the firmware, I once again booted Ronin and shut it down, quit ASS2 and rebooted it.  But this time I disconnected the USB-C cable from the GH5s (I just let it hang from the port on the gimbal so there was some balance weight).

This time when I went to ASS2, I was told that I needed to update the firmware.  I clicked update and the process went perfectly.  Now I see the correct firmware version in the Ronin app on my iPhone too.

SO Make sure your camera is not plugged in to Ronin when you do the firmware update!

Hi Mabou2, glad to know you have updated the firmware successfully and thanks for your sharing, hope it will help other users who have the same issue.

DJI Mindy Posted at 2018-9-6 02:54
Hi Mabou2, glad to know you have updated the firmware successfully and thanks for your sharing, hope it will help other users who have the same issue.

Hi Mindy,

Thanks for this reply.

Unplugging the USB camera control cable from the camera instantly turned a 100% failure rate to a success.

Of note, there are now two posts from me in these forums that directly relate to the USB cable being plugged in to the camera, causing strange problems with the Ronin-S.  The other post related to the gimbal going ballistic when there was also a 5.7" monitor connected to HDMI AND the USB cable connected from the GH5s to the Ronin.  
Seems to me that there is a common theme to these two posts, likely related to either a power draw on the camera power port, or some "ghost" circuit that is causing some sort of feedback on the Ronin.

Had the same issue, stuck at 98%, but after many tries, Ronin has been updated without unplugging USB cable

Mabou2 Posted at 2018-9-6 05:17
Hi Mindy,

Thanks for this reply.

For the HDMI monitor issue, we have forwarded to our engineers and will keep you updated in another thread.

Mikex Posted at 2018-9-6 23:23
Had the same issue, stuck at 98%, but after many tries, Ronin has been updated without unplugging USB cable

Thanks for your feedback, glad to know you have figured it out, please keep us updated if there is any other issue.

No problem Mindy.  It has been suggested by others that it might just be a coincidence that the firmware successfully update after unplugging.  Others had multiple failed attempts then finally a successful attempt.  So I MIGHT just be fooled to think the cable pull did the job.