Only One HDMI Input Works

I assume that you enabled hdmi ports within settings.
I would connect box to another TV and within settings in box make sure that box outputs either 720p or 1080i.
Your TV doesn't accepts 1080p .

Make sure your X Box is switched to component and not hdmi.

Hook your Xbox to tv via HDMI, then hook TV to reciever through digital optical or composite cables. If you try to get your picture through receiver first, you may get picture and sound but, sound may be delayed and picture might not be the best. Bettter to run through tv first then provide sound to receiver.

I have the same problem.  It only occurs with my HD DVR (HDMI cable), not my blue ray (HDMI cable), or my xbox and wii (component video).  Video and audio cutout is random and drives the family nuts.  I am desperate for a solution.

Hi.

To start ensure that each time you connect or disconnect the HDMI ports both TV and connected device are off.

Also ensure that HDMI input is active, as detailed here.

HDMI connectors carry voltage, and connecting the HDMI cable while TV or device is on may easily damage the HDMI port, making it unusable.

The HDMI 3 and Component 3 are separate input. The component input may work, and HDMI port may still be defective.

To test the port do the following:

Disconnect TV power cord, and connected device (eg. Receiver, DVD etc.).
Leave units disconnected for five minutes.

While power is disconnected, test connecting on port three a device that was previously working on HDMI 1. Also use a cable that you know is working.

Connect back power with HDMI cable already connected. If HDMI 3 is still not detected, then the port is defective.

In that case ring Pioneer at the number listed on the owners manual.This model is often advertised as only two HDMI inputs. Call Pioneer to ensure the third port can be enabled.

HDMI version is 1.3 in your receiver.The current version is 1.3b. I would suggest calling Pioneer cust assistance and see if there is a firmware update. Your unit has a 2 year parts & labor warranty. Their # is 1-800-421-1404 It sounds like a CODEC issue. Hope this helps

why hdmi input wont show up

I've posted this other places. Hope it helps.

My HT-S6100 had a similar problem with my DVD player and some times with my Cable/DVR box. The signal wasn't getting received at the TV. So, first I changed the input jacks my DVD and Cable box are plugged into on the receiver (e.g. from HDMI 1 & HDMI 3 to HDMI 2 & HDMI 4). Second, I reprogrammed the Input Assignments to match (e.g. HDMI in 2&4). Third, I deleted any Input Assignments that weren't applicable. For instance, I'm only using HDMI connections, but there were Digital and Component Input Assignments programmed in. When I say I deleted them, I actually set them to "----" (just scroll through the options and you'll find this.) Finally, I turn on my video/audio sources (PS3 in your case) and let them load/warm up before I turn on my Onkyo receiver. It seems to be working. Good luck.

I'm thinking the Comcast DVR box maybe putting out weird HDMI signals and the TV can't translate it. I would call the Comcast people on this one.
In the meantime, I would try finding another source the uses a HDMI cable to rule out the TV as the problem. Basically, testing the TV to see if the problem still happens when you use something else than the Comcast box. Try a Blueray player, Playstation 3, or Xbox. Just something that uses a HDMI cable.

Hook up Composite / Component Monitor Out wire from receiver to TV video input because receiver will not change analog input into HDMI
You need to connect receiver and TV through analog video terminals as above.
Actually you are expecting that receiver will convert DVD player and Xbox analog video input into digital HDMI signal for TV and This is incorrect.