The receiver thread will answer your question, and the others will also help.

RM-AV3000/3100 NEWCOMER’S PACKAGE-WELCOME-CHECK THESE OUT (IF YOU HAVEN’T ALREADY DONE SO) AND SAVE YOURSELF SOME PROBLEMS

AVOID SYSTEM CONTROL PROBLEMS

HOW TO LABEL, CHANGE OR HIDE BUTTONS

CHANGING BATTERIES (May not apply to RM-AV3100-time will tell)

AND IF YOU HAVE A SONY RECEIVER:
CHANGING YOUR RECEIVER AND REMOTE TO AV1 (or AV2) COMMAND MODE

FOR RM-AV3000 OWNER’S: REMOTE CENTRAL RM-AV3000 FORUM REVIEW