My Mavic fly fine in vision mode indoors and it is as stable as usual. However, every time I use RTH, after it descend to around 25 metres, the bar on the top left of the screen will go red saying ‘Vision Sensor Error’ (the Mavic didn’t drift or anything at all). The message stays for only 1-2 seconds before disappearing and the Mavic fly fine again. This do not happen when landing manually, may be something to do with precision landing? Is this something I should be worried about?