Your issue sounds like some kind of funky (HDMI) CEC errors. CEC seems pretty hit or miss to me (and for many others in related forums). Equipment may all work nicely together or there may be incompatibilities. Some spin CEC perfection while others share all kinds of "NOT just works" issues with it.
It sounds like your

TV may have some kind of CEC priority over your BD player. Basically, if

TV is "awakened" or anything "pings" the

TV, it seems to be taking over your screen (via CEC) as if you are purposely wanting to switch to it from your BD screen. Best I know, there is no way to adjust CEC priorities.
Unplugging the HDMI cable breaks this CEC control (from

TV) but that's an aggravating solution(?).
The actual problem could be in a variety of links in the chain:

TV CEC, BD CEC, TV CEC, receiver CEC, possibly even some fault in any of the cables, etc.
A few things you could try:
- Swap cables from
TV to receiver and BD to receiver and then see if
TV still seems to take priority (see if you can replicate this
TV taking over when watching BDs). If that solves it, one HDMI cable might be bad. Of course, you'll then want to test it the OTHER way: can you make BD "take over" when watching something on
TV? I don't recall ever seeing anything where a cable could control CEC priority- or even if there is something to CEC priority- but it's an easy enough test if you want to do it.
- If you happen to have an older
TV lying around, temporarily slug it in in place of the one you have and see if the problem still occurs (this is just testing one
TV against another, while leaving everything else the same). If so, you might try turning off CEC on the original
TV, rebooting, then turning it on again, repairing it with the receiver.
- In lots of deeper CEC online help forums, there is also discussions about the ORDER of connecting things via CEC mattering. In other words, each link in the chain may depend on when one thing is connected vs. another. The ambiguity therein is immense, as there's not typically anything that guides you to an ideal order... unless you just happen to find someone with the exact same combination of equipment who have tested this and figured it out.
Ultimately, I've come to a conclusion that CEC is just not mature enough to reliably "just work" for everyone... except perhaps in very simple setup scenarios. So I've shelved it (turned it off in everything) and shifted CEC-like controls out to a universal, learning remote capable of running macros. This remote is programmed to replicate what I want the CEC code to do, but the remote allows me to control WHEN those commands are executed and know exactly WHICH commands are being executed. End result is CEC functionality without hoping CEC works as I expect it to work with various equipment from various companies.
I've opted for universal remotes from URC Inc that have a LED window next to some buttons. These can be programmed to do anything. I allocated one of those buttons as "setup" and that gets the macro sequence to switch from one player to another. In your example, if I wanted to watch BD, I'd click the BD button to put the remote in BD mode, then this "setup" button to switch the receiver to the proper input, etc. When I wanted to watch

TV, I put the remote in

TV mode and then hit the "setup" button to switch inputs to

TV and so on. This makes it all "just work" and is simple enough for even the most non-techies to understand how to control the home theater and watch whatever they want to watch.
The fundamental difference is that I can very specifically KNOW what commands are being executed which I can't with "black box" CEC "magic"... thus, in a problem like yours, you can't even hardly begin to know where to start looking for a problem to resolve. It could be this. It could be that. It could be cables. It could be a combination of equipment that just doesn't work properly via CEC. Etc.
If you try a few suggestions and nothing resolves the issue, you might consider my solution. Maybe there will eventually be a CEC-2 or similar that really pins down a standard that will "just work" with various kinds of equipment. Until then, there seems to be more "luck" than standards in play.