First find out if the Blu-ray player works when plugged directly into the TV. That'll tell you if the player and associated cable are compatible with the TV. Use the cable that you're using to connect the player to the receiver. If that fails, then the problem is in the player or its cable.
Another thing to try is a different HDMI input on the receiver, just in case that particular one is defective. The labels are primarily for your convenience. They all should work the same.
Often the startup screen of a Blu-ray player is low-resolution, but later images and on-disk menus are high-resolution (1920x1080 aka 1080p). There are a variety of things which could prevent a high-resolution video signal from being shown: poor cables, receiver settings, incompatibility with the TV resolution, etc, Cable and Satellite boxes usually output low resolution video: 480p, 720p or 1080i. I suspect that's the case for the video associated with the iPod, too.
Marantz SR7009 avr + MM9000 amp --> Atmos 7.1.4
Fronts=NHT 2.9+AC2, FH+TM=DefTech PM1000, LCR+TM amped