How to fix black screen and record both system audio and microphone at the same time in Camtasia
This is a video explaining one workaround to fix the problem where camtasia will record audio, but only a black screen.
Also, this can fix a problem where you cannot record both the system audio and the microphone input at the same time.
Should have mentioned this in the video, but to record the system audio and the microphone at the same time, go into the camtasia recorder window, click on the arrow next to "audio" and make sure "microphone" and "Record system audio" are both checked (make sure you have all the correct audio settings set up, found in "options").
Should look like this : http://i.imgur.com/MZsOs.jpg
There is a chance that doing this may not work, but uninstalling divx as suggested in the video fixed that up for me.
Using:
Camtasia 7.1
Windows 7 64-bit