I have a SystemLink 4 remote, and need to control an A/V receiver. The
instruction book has a list of audio codes, but the instructions are screwed
up.

The only device buttons are TV, VCR, Satellite, and AUX. Instructions say
audio devices can be assigned to AUX.

Instructions for assigning other devices to AUX say press and hold Code
Search Button until light comes on, then press AUX, after which the light
will blink and stay lit. Then the instructions say to PRESS THE BUTTON FOR
THE DEVICE you want to program. But there is NO AUDIO BUTTON!

I've tried just pressing AUX then putting in audio codes, but nothing works.
Tried on three different brands of A/V receivers.

Anybody know how to make this remote work audio? Thanks.