Home Theater Questions? Ask a Technician for Answers ASAP
Hi and welcome to JustAnswer,Thank you for the question and your patience. Should you still need assistance for information purposes only...Initially, preliminary considerations / tries:
The findings of "...same results from the TV (HDMI), but get somewhat better results from iPod or Wii (RCA cable inputs)..." are significant as it would almost always point to an internal hardware issue.
Have you considered/tried a RESET?
Yes, re-try the RESET. A reset is both a test and a try of a fix. As it implies, a reset would force the unit to revert back to factory defaults removing glitches and config errors but would include memories, presets and user preferences. After a reset, the initial setup would have to be performed. If have not been done and should you venture to try: While in Standby mode go to / perform INIT....ALLPlease click HERE.
May have to be done a number of times.
This is very critical - a reset however would not be corrective of an internal hardware concern; but it would be confirmed. In some instances, it may even expose other issues.
If not corrective, are you then considering a DIY (do-it-yourself) repair approach? If yes, do you have access to and familiar with a multi-meter and even a soldering iron?
Equally important, could you make use of the repair/Service Manual or at the very least, the schematic diagrams?