FWIW, it's not called an 'AV amp'. You presumably are working with an (integraged) AV receiver. When anyone refers to an 'amp', it is normally used in the context of separate components (amp & pre-amp, etc.). Knowing the model number would help too, btw (nudge, nudge).
It could very well be combination of issues. Some BD players & specific blu ray titles (e.g. discs) can cause issues like you are describing. YMMV. Ditto for HDMI connections/ports. I do the same thing when I troubleshoot such issues for people- remove the 'monkey in the middle' connections (switches, etc.), then go direct to the HDTV and see what happens. Then, ideally check another HDTV (or two). Fun times, eh?
Just to be clear, do you have your system connected as follows:
Blu ray player (HDMI out) -->> (HDMI in) AV receiver
TV source (HDMI out) --> (HDMI in) AV receiver
AV receiver (HDMI out) --> (HDMI in) HDMI switch
HDMI switch (HDMI out) --> (HDMI ink) SONY HDTV
"" "" (HDMI out) --> (HDMI in) open/projector
Ok, so this should be a challenge... I confess I'm completely baffled at what happened. I will try to describe it by steps:
1 - I have my Samsung Blu Ray Player and TV signal connected to a Sony AV amp.
2 - My Sony AV amp then connects to a hdmi splitter with two outputs (one is unplugged, and the other goes to the TV). I use this so I can connect my projector whenever I want to.
3 - Everything works great, and today I tried to watch a 3D blu ray and it was cool. Then I tried to watch a regular blu ray disk and suddenly the TV (Sony w805b) won't get any picture from the Blu ray. It's as if it was unplugged... I immediately unplugged the hdmi splitter and connected the TV directly to the AV amp to get that out of the equation.
4 - So I decided to try different blu ray disks, but none worked... until I put the 3D blu ray disk again, and it worked! So I went back to all the other blue ray disks and it won't work again!! Not even the BD Player menu!!! But when I go back to the 3D disk, it works again...
5 - I tried the BD player on another TV and it works great. No problem at 2D or 3D or whatever.
6 - I don't know what the hell happened, but the TV regular signal works perfectly. The only thing that won't work is the blu ray player!
WHAT THE HELL HAPPENED?!?

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