Sony TA-AN1000 loud bang when I switch TV on

[mpezzer]

• Recently purchased the 1000 receiver from Sony. It's connected to a Sony X95L 65" TV using new 48 bit HDMI cable, using the eARC input. 

The receivers standby modes are all switched off.

The TV's HDMI sync features are switched off as I don't want the receiver auto switching on every time I watch TV. Firmware is up to date on both units.

The issue I'm having is, when the TV is turned on from standby the receiver makes a loud clunk noise. This also happens when turning the receiver on/off.

Can anyone tell me if I have a faulty unit? Or if there's a way to stop this?