Spurious surround content from VSX-LX305

[Stokestack]

Hi all.

I just picked up this receiver. My main source is an Nvidia Shield (via HDMI). So far I'm pretty happy with the experience.

The Pioneer is installed in exactly the same setup as two previous receivers: an NAD and a Denon. I'm now having a problem that I didn't have with either of those: distorted, spurious content in the surround channels. I'm watching NBC News and Daily Show with the YouTube app right now and getting what appears to be distracting, distorted center-channel overflow in the rear channels. The surround mode is DDD 5.0 (I have no subwoofer).

Aaand as I was typing this out I went over and pressed the Surround button on the remote until I got to "auto-detect." This eliminated the crap in the rear channels. But... what was it doing in DDD mode, then?

Thanks for any insight.

 

[markthefixer]

Something wasn't right, and auto-detect sorted it out. Probably reading the wrong part of the data stream. But I'm NOT an expert at that.

 

[Stokestack]

Yeah, it's probably time to read the docs, too. I'm just relieved to have simple niceties like an on-screen status display and 1080p video, after suffering a wretched experience with NAD.