I am having the same problem. Although I don't have all the codes for my universal remote MX-900, I have found some that work such as stop, play, etc. My problem is it only work when the remote is used in line of sight. I am using universal remote RFX-150 to broadcast the signal.
I am having problems controlling my BD-P2500 Blu-ray with my Universal remote controls (MX850, 900, 980) via an IR repeater or an MRF. I can only control it through line of sight. I also have a BD-P1200 and do not have this problem. Anyone else experiencing this problem or have a solution for it? I have tried learning the codes, but still no results.

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