I have to return yet another universal remote because I can't get it to learn some Marantz commands. I have the 7300 Marantz receiver, and at the bottom of its remote, are several buttons needed to switch the receiver over to various modes - eg. VCR, DVD, CD, etc. So far I can't get a universal remote to learn those buttons. Which makes a universal remote kind of pointless if you need to have the receiver's remote around to change the receiver's sound source everytime. Am I doing something wrong, or is this a typical problem?