Webcam laggy - Logitech C920

I've just purchased a new Logitech C920 webcam.

I've installed the recommended s/w from Logitech on my 2016 Macbook running 10.14.6 and plugged the camera into a USB3.0 connection.

I now have a lag of at least one second - sometimes more - with the camera capture. 

I have searched online for a solution, and the problem also occurs with Windows, and there's a way on those machines to change the capture file stream format. I cannot find the same setting on OSX.

Has anyone solved this?

Any and all help much appreciated.