The only other thing I can think of is that the command is being sent too soon after the TV is turned on.

If you manually turn on the TV and immediately press the input 2 button, does it work?

If you need to delay the sending of the command, you can put some keys that don't do anything before the input command.

But this probably won't help because you said it doesn't work even at the slowest setting, so now I am stumped.