Apart from the quack, which is usually a giveaway, look for a little curl at the end of the tail feathers. Only drakes will have that.
The noises in the
video are definitely drake sounds, so my take is that he's a non-curly tail drake.
We have a female Pekin who usually just makes a quiet sort of squeaking sound and only quacks when she's either excited or lonely and wants attention (her mate died last month so that happens a lot more than it used to).