The latest update from elgato fixed a really annoying bug with obs but with this update this problem comes to a few users.( i read this problem since the last week a few times) i also have some problems to get the elgato in obs to work but it should work after a few tries. my way to get it to work:
1 Start elgato software and make sure you see the input
2 Close the software and start obs
3 defining custom resolution for your elgato device (for Example 1280x720 60 fps)
4 Now should it work if not replay the steps.
Alternative you have the old elgato you can go there
https://help.elgato.com/customer/po...elgato-game-capture-hd-software-release-notes and load the oldest version (
1.42.24). I used this version for the last 2 years and this version worked perfectly for me. i just use the current version because the 64bit driver. except from the start problems the newest version is also good.