Purple & green static on TV (1 Viewer)

[hvjackson]

I'm getting intermittent purple & green static on my TV and was hoping someone could help me do some troubleshooting. I have HDMI cables going form my Mac mini -> Denon receiver -> LCD TV. The cables are reasonably new and appear to be high quality and in good shape. The problem is intermittent -- maybe once every week or two -- and comes and goes on its own. I've attempted to isolate the problem by rearranging cables, taking the receiver out of the loop, etc, but the problem disappears and I can't reproduce it with fewer variables. Any thoughts what might be the problem? I'm happy to buy new HDMI cables (and may do that anyway), but obviously the rest of the system isn't so easy to just blindly replace.

 

[Gregg Loewen]

static, or sparkles, usually indicates cable issues. Perhaps too long of a cable run, or poor quality. Good luck

 

[hvjackson]

Alright, I might as well just buy new cables. I'm a little skeptical of that being the issue, since 1) the cables are short, relatively new, and appear to be in good condition, 2) the problem comes and goes without any movement -- nobody is jostling the connections. That made me think it was more likely to be a problem with an electronic component on the fritz. But cables are cheap so I'll see if that fixes the problem.

 

[Joseph DeMartino]

Sound like your TV might be under attack by the Drazi.

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You haven't been watching a lot of Babylon 5 on DVD lately, have you? On a more serious note, I remember my boss recently mentioning that he had what seemed like a grounding issue going on when he had his Mac laptop (sorry, don't know the model) and another device connected to his TV at the same time. The two devices had ungrounded power cords, and he thought this was part of the problem. Anyway, while he looked up that issue on one of the computers in my office when we were discussing it, and I know that some of the results he got searching "Mac, HDMI, grounding problem" were about the Mac-mini, not his laptop. Might be worth looking into, as there were a number of results and it looked like a known issue. Regards, Joe

 

[Jason Charlton]

There are lots of potential sources for electronic interference. You can start with the easiest - are all components plugged into properly grounded outlets? Also, do they all share a circuit? What about your subwoofer - if it's a powered model and pulls lots of power from the same circuit as the rest of the gear, that could conceivably also contribute.


Finally, and I'm completely grasping at straws here, what about the laptop battery? I used to notice that anytime my portable satellite radio receiver was plugged into the car and charging, that I'd hear a high-pitched whine in the music that was being played. Have you noticed any difference with the laptop plugged in vs. running off battery?


There's always a chance the cables are the culprit, but as you and Gregg indicated, that generally happens more frequently with long runs.


Hope you figure it out. Good luck.

 

[hvjackson]

I checked the outlet and surge protector with an outlet tester, and everything seems properly grounded. The TV plug is grounded, but the Mac mini and receiver plugs are only 2-prong (not sure why). The Mac mini has no battery (it's a small desktop computer), so that's not an issue. However, while poking around back there I noticed that the power cable on the TV was unseated about 1/16". Perhaps the ground pin wasn't fully in contact? Anyway, perhaps this was causing a ground loop. The new HDMI cables just arrived (thank you, Amazon Prime!), so I might as well install them.