Is that "at" absolutely necessary here? Seems redundant to me.
Jeg ser han spiser sin mad = I see he eats/is eating his food ... unless the speaker wants to stress the fact that he is closely watching???
The pronunciation of "mad" really puzzles me here. It sounds like something between "mell" "mull" and "mall"(?!) Is that right or is there just something terribly wrong with my speakers or, indeed, hearing?
The "a" is pronounced as the A in "hat" (in Received Pronunciation) and the "d" is pronounced similarly to the "th" in English, just form the tongue as though you're saying "L" in the back of the mouth, with your tongue between your teeth.