I recently picked up a reconditioned Slingbox 500 from Newegg and have been trying to get it working with my AT&T Cisco ISB 7500 PVR.
First, my profile doesn't acknowledge the unit was reconditioned and reports its activation date as October 26, 2014. That means I didn't get the 90-day warranty Sling claimed to offer with these units.
Second, I cannot get playback through the device. When I use the recommended component+HDMI configuration, the receiver throws a failed HDCP integrity check. In this case, I used two new HDMI cables-- The one provided with the Slingbox, the second, a pro-quality cable from my usual tech vendor. My cable works perfectly when connected directly in to the receiver. The failure point is between the receiver and the Slingbox, and can be recreated using both the Sling-provided cable, and a second known HDCP-compliant cable. If I disconnect the cable between the receiver and Slingbox, the HDCP failure goes away, but when trying to watch live TV, the Slingbox complains about not having an HDMI signal.
If I use only the component input, I get no signal at all, and the Slingbox 500-specific features (Gallery, etc) complain about not having an HDMI signal.
The Slingbox looks nice on my A/V credenza, but I'd be happier if it worked.