Hi @Seb,
Are you saying you’re now unable to change the video device from the companion web interface, or are you asking how you could change the video device from QGC?
If both cameras are still being detected you should be able to swap between them in the web interface. At this point QGC only knows about one camera at a time, so you can’t swap between streams from within QGC unless you set up a second stream on a different port (in which case you can swap the port QGC uses in order to access the other video stream).