I've got a Harmony 670, a HK AVR-745, a Motorola DCT-6412 III cable box, a Toshiba HD-XA2 dvd player and a Pioneer PRO110FD plasma.

problem is, the remote isn't turning the receiver off from the TV activity. i've checked and double checked the remote setup and i know it's correct, and the on/off commands from the device menu on the remote work properly, but when i hit off from watching TV, the sound cuts out for a few seconds and then comes right back on, i have to hit the device menu and manually turn the receiver off.

if i hit off from the dvd activity, however, both the dvd player and the receiver do turn off properly.

the difference in the two is the cable box is set to stay on all the time, the dvd player is not.

any ideas?

Somewhere in the setup of the activity/device (can't remember where), you can customize the delay between button presses. You'll probably want to increase it. The remote might be sending the "off" signal to the receiver too quickly.