720 x 576 is standard definition (SD) PAL or SECAM. So for whatever reason, when using your other capture process, it's only able to work with SD. Or, is reverting to SD due to an incompatible HD signal.
Check to see if you have any control over the HDMI output in terms of being progressive vs. interlace (1080p vs 1080i). Sometimes external recording equipment can only work with interlace.
Thank you for your reply. The settings on the Canon Legria HF-G25 is pretty limited, since it's a prosumer camera & not a professional one. The settings that can be changed on it (that's related to progessive & interlaced) is the frame rate - options of either 50i (Standard 50 frames interlaced) or PF25 (25 frames progressive). Other than that the HDMI output can be set to 1920 x 1080, but no option is available to switch between progressive or interlaced here. Once a display or video capture device is connected to it, it will change the HDMI status automatically depending on what camera it is connected to.
Will the actual HDMI cable make any difference if the cable is not up to spec? I've used different lenghts with the Black Magic Atem Mini with much success, but with thie Razer Ripsaw video capture card it seems to have a problem, even with short 3m to 5m HDMI cables. When a GoPro camera is connected to the it, it sends 1080p video without any problems. There is something on the Canon camera end that is the problem, but I'm not sure what it could be. The same video capture card was used previously with a much cheaper camcorder without any problems, so it's really confusing.