Onkyo 606 minor questions

[Automission]

so I'm wondering, what sort of warranty does my 606 come with, as I've owned it for nearly a year now, and never really considered it.

The reason I'm asking is I'l find sometimes when turning it on and the connected device E.g 360/PS3. It'l sometimes display the connected device fine, but then it'l flicker and keep cutting out to a black screen, displaying it briefly, then a black screen. It does this for maybe 30 seconds, then it displays fine and can be used.

A similar problem is with the PS3 the display will stutter for the first minute, sort of flickering but not as bad as the first, then again, it's fine. Both 360 and PS3 are connected via HDMI cables.

Are these hardware faults that need repairing, or just something simple like a loose cable, or even normal operation?

So to clarify, the 360 will boot up fine, then after a few minutes it has a "handshake issue" and keeps flickering with no signal, then it'l be fine.

The PS3 does very little like this, will always display just has minor interference/juddering for a few seconds.

the Sky HD box works fine, turn it on first time it works, no loss of signal, no handshake issuses.

This makes me think it can't be a hardware fault, given one of the three works fine?