Might try playing with your audio/video encoding config on the camera.. iirc I had to change my big black face dahua's audio encoding to get it to play.. it did not like whatever format I had it at and just gave a blank display until I tried playing with encoding settings.. I want to say it did not like uLaw but worked fine with PCM, not that I have any speakers hooked up right now but it did throw a wrench in things when I started off.