I have never had problems with DirecTV receivers. This one is giving me some grief.

There is no RF interference with an MRF350. But this MX990 sometimes gets a command and sometimes does not. I have adjusted the IR position and the IR level. I even embedded The emitter inside.

As you know, this is a networked box. My one other experience with a network DirecTV box produced very laggy responses, to where the client sent it back and got one that's connected to coax. Is this likely my problem here also? Are these networked receivers just more difficult to control reliably? Wish I had a standard box to try.

ALWAYS use the HR21 Codeset wth DTV

Code 173.

I have a feeling he probably tried that but it's worth pointing out.

I haven't ran into a C41 but was surprised at how sensitive the mini was to IR.

I've had to use the tape/pinhole trick with G and URC.

173 forever and ever, always works, but now...

Maybe I will try the pinhole. Currently, the emitter is emedded. I have not seen any difference in the emitter position or IR intensity, but I guess I have to try everything.

Maybe try putting an IR cover over the emitter, or since the emitter is now inside, a few layers of black tape over the window? I've got this same scenario working with no problems. Could it be that there's some other IR in the room that's only affecting the C41?

I suggest a few layers of black tape since what's opaque to us isn't always opaque to IR.