[Link: remotecentral.com]Try to use the preprogrammed codes where possible. And, if you are learning, make sure you HOLD THE BUTTON DOWN until the RM-AV3000 beeps.
I *have* had success learning parity bit codes for my Philips TV with the RM-AV3000 or RM-AV2100. Although the set *will* operate with remotes that don't support parity bits, there's a lengthy delay required between simultanous key presses (such as up-up-up).
With a learned code on a remote like the MX-500 or UC-525, I need about a one second pause between each attempt to send "up". But the RM-AV3000 operates the set just as fast as the original remote, leading me to believe that it does detect and process Philips-style parity bits given the chance to...
Of course, since I don't have any device that TRULY requires parity bits (like you do), I could be wrong.