Always a good idea to follow forums pinned posts/rules on asking for help
OBS Studio creates a log file each time you run it which contains very useful diagnostic information. Without a log file, it's much harder for any support volunteers to figure out problems and your post may be ignored. To upload a log file, go to the Help menu > Log Files > Upload Last Log...
obsproject.com
My recommendation
- make sure your Audio connection is working in the Operating System first, before even starting OBS
- I'm assuming you have HDMI out of camcorder to a Capture Card, connected by USB to laptop, right? (a HDMI output port on a GPU card or laptop can't take an HDMI signal in)
If USB 2 port, then you'll have potential bandwidth issues
Make sure capture card drivers up-to-date and configured correctly