purchased new vizio, have 612 w/6.4 if uhf pro remote. Works fine with tv functions, will only control receiver from around 2.1 inches away. I have read enough to know that you can change the remote code. Have done this a few times with limited success. Sometimes works for an hour or a day...then back to the 2.1 inch rule. Sooo frustrating. Foreign tech support has only recommended changing remote code. Help!