I just picked up a Sherwood RD-6506 as part of a slightly upgraded setup. But I'm having problems getting the digital inputs to play nice.

I have hooked up the Amazon Fire TV via HDMI to Video 1, and from the Monitor to HDMI 2 on the TV. 

What I get is very choppy audio - it cuts out for a second, comes back for about .5 of a second. 

This also happens when connecting via optical input, although I can get optical to work when the CD input is selected. 

I have ruled out the following as sources of the chop: 

- The Fire TV - plays fine when plugged directly into the TV via HDMI

- The HDMI cable(s) - I have used three different cables in all six different potential configurations. All work fine Fire TV - TV, but error remains in all Fire TV - Receiver - TV configurations. 

- The TV I can connect via analogue and optical out to the CD input ok, and the TV speakers also play via HDMI from the Fire TV fine. 

Not sure if I am missing a setting? The manual is not helpful, nor is google. 

It would be great to get this working in order to get DTS working and reduce some cables. 

Thanks!