Hi Paddy, thanks for that. I’m afraid I’m still very much confused :-/
Had a look at the QT Inspector as you’ve suggested and here are the credentials:
H.264, 1920 x 1080, Millions
Linear PCM, 16 bit little-endian signed integer, 2 channels, 48000 Hz
Current size: 1276 x 718 pixels
And now???