Question: Does it support 1080PI 50 input?
Answer: Yes, it supports. 
1080P 50 camera video input
1080P 50Hz monitor receiving (Please check the below video link or below youtube link)
https://youtu.be/bbX8exaUu0M
Question: Does COFDM-904T have an audio transmission function?
Answer: If the audio from HDMI, then it supports, it does not support CVBS audio input, only have CVBS video input (Yellow). Please check the below video.
https://youtu.be/-2ine7z1a70
