If the flight control app feed is black: First, try disconnecting and reconnecting the cable from the tablet. If that doesn't fix it, try restarting the flight control app. If that still does not work, restart the drone and controller.
If you've recently updated firmware on any of your hardware: While uncommon, you could be experiencing a firmware mismatch between devices. Check your controller and camera firmware as applicable to see if they are out of date with your drone.
If your M210 is having issues with video streaming: The M210 requires that some cameras be connected to specific positions on the drone. For thermal cameras, make sure the XT1 camera is mounted in position 2, or the XT2 is mounted in position 1. If you are using an X4S camera, make sure it is connected to position 1.
If you're connected via a WiFi connection, try switching channels (2.4GHz vs 5.8GHz) for either the WiFi or the remote controller. This can especially be an issue when flying with two controllers in a master/assistant setup.
Make sure viewers are on an up-to-date browser: Older browsers may not support DroneSense streaming video. Make sure you're on the most up to date browser version available. On iOS, make sure your device is using iOS version 12 or later.
If video won’t play at all: Check internet speeds for all devices and confirm that you’re using Chrome or Safari to view Operations Hub. Also, make sure your organization's IT department has not blocked video streaming services (check YouTube) or otherwise has restricted usage on the network. Try connecting from a different network, such as a mobile hotspot.
If the drone video feed is black: First, try closing and restarting the video feed in Ops Hub. If that still does not connect, notify the pilot that they need to restart the Pilot application. Make sure the pilot performs the restart from a safe place so as to not lose track of the drone.
If you've never been able to view video feeds in Ops Hub, you might be running into firewall security issues. You can read more information about Firewall Security in this article.
If your video has high latency or is choppy: Confirm that your pilot is using a recommended tablet model and is not overheating. This also can happen in areas with high WiFi or LTE traffic, such as large crowds at public events (concerts, sporting events, and so on).