My CS8 is drifting quite a lot when on gps hold. Is that has something to do with the gps not being at the center of the copter? Do you use some different gps settings? Because my other MK is more position locked.
How much drifting? I've seen the home postion in the OSD drift my many feet while it was sitting on the ground.
CS8 is going slowly around in circles in about 4m radius and has 6 satellites. On the same spot MK hexa is in position in about 1,5m radius. As you mentioned movement on the ground with the OSD, there is the same behaviour on my MK kopters. I'm asking this because with DJI you must set offset for the GPS to be more accurate.
You might take a look at your mini SD card and see what the compass values are being recorded in the gpx file. Also what number are you using for your gps gain? Cheers, Jeff
Small circles.... this looks like magnetic issues. As Jeff said take a look at the log for errors also, it's on the end of it. I'm using my CS8 with the GPS gain at 98% and it's locking in position even under heavy wind. Good luck,