I have seen this message on my MA a few times and it does not seem to be any issues.  I do bring it back when I see this message and land it, check it out then re-fly.  Not sure what it means or how concerned I really need to be when I see this.

Any help would be awesome.  Thanks.

"In Flight, working IMU encounters attitude exception, please slowly get craft back if craft behave abnormally

This issue may come from any reason: home point did not recorded (at least 11 satellites lock), strong interference caused by strong wind or near metal structure or even your flight attitude is lower than it recorded. My suggestion is if you flight in sight, slowly and gently bring it back manually. If out of sight, open map and flight it back to your location manually. Do not push return home if this error appears usual.

Interesting that the error shown here is also shown in all the crash logs we've seen in the past few weeks. Either there is a connection there or the MA is spewing this error all the time and people simply don't notice.

Hi, sorry for the inconvenience. If you encountered that issue it might be that there's something wrong with the IMU and I would recommend re-calibrating the IMU and compass for accurate information on the DJI GO 4 app, ensure that there are no interferences on the location to avoid an interruption to the connection. Please let us know if the issue will persist.

What is the high you flying when see this message? Wonder is it appear when flying too low.

DJI Tony Posted at 2018-8-20 12:17
Hi, sorry for the inconvenience. If you encountered that issue it might be that there's something wrong with the IMU and I would recommend re-calibrating the IMU and compass for accurate information on the DJI GO 4 app, ensure that there are no interferences on the location to avoid an interruption to the connection. Please let us know if the issue will persist.

Re-calibrated the IMU and that seems to have helped.  Thanks.

GDL Posted at 2018-8-20 20:08
What is the high you flying when see this message? Wonder is it appear when flying too low.

It did not make any difference what flight AGL I was.  Seemed to pop up when ever....I did re-calibrate the IMU as suggested by DJI Tony and that seems to have helped

ProQuad Posted at 2018-9-20 04:26
It did not make any difference what flight AGL I was.  Seemed to pop up when ever....I did re-calibrate the IMU as suggested by DJI Tony and that seems to have helped

IMU exceptional heading usually occurs when you have conflict between compass and IMU.

Example: if you put your craft down on the ground at launch, start up and lift your craft by hand turn 90 degrees both your compass and IMU will move in sync 90 degrees.
If however you put your craft on the ground at launch and there is magnetic interference, your compass will change its heading, this problem will not always show on your app, when you take off and clear magnetic interference, your compass will return to correct heading, but because it has moved so will IMU , your IMU will no longer be synced with compass as it should be. You will then get a warning exceptional heading, soon after this you could receive compass error, then gps gets dropped and aircraft goes into Atti mode. This is where exceptional heading comes from.
So be careful around any possible magnetic interference, you shouldn’t need to either preform compass or IMU calibration, but it won’t do any harm.

ProQuad Posted at 2018-9-20 04:25
Re-calibrated the IMU and that seems to have helped.  Thanks.

Hi, Thanks for your response. Glad that the issue has been sorted. Please avoid flying the drone in a hazardous environment to prevent an incident. Thank you for the support.