I've recently helped my brother piece together a somewhat low-end front projection setup for his basement theater. He's feeding an Optoma H31 projector through a Denon 2307 receiver with a Moxi HD box (DVI-HDMI) and a Philips DVP-5982 DVD player (HDMI-HDMI). The short (3') cables are Monoprice 26 awg HDMI and the long run (30' + HDMI-DVI adapter) is Monoprice 24 awg HDMI. All signals are passed in 1080i and converted to 480p by the projector.

We're seeing sparkles, most prevalently on bright and solid white images, regardless of source. This is usually associated with long HDMI runs. My first recommendation was to add a Monoprice HDMI Equalizer. This is where it gets strange... this fixes the problem, but only for about 2 hours at which point, over the course of about 5 minutes, the signal degrades to the point that it is no longer passed at all.

We first assumed it was a faulty equalizer. Monoprice sent us another which did the same thing. The results are identical regardless of what location in the cable stream the equalizer is located. I don't think it's a heat issue (at least not due to surroundings) as the equalizer has plenty of air space around it.

Is this a known design flaw/fault of this particular equalizer? Are there others on the market (reasonably priced) that do not have this flaw? Would a powered HDMI equalizer do any better? Any in particular you guys would recommend?

Would reducing all signals to 480p (native resolution of the projector) help by lowering the amount of data being passed? Since the projector is 480p native, is there even any advantage to sending it a 1080i signal?

Do we need to step up to a 22awg cable? Or one with a built-in equalizer?

My brother isn't all that picky, but this issue is an annoying one. I feel bad because he's constructed this room for this purpose and the gear recommendations were all mine (which I think we did well considering his VERY meager budget).

Thanks in advance :)

Switching to 480p will definitely lower the amount of data being passed over the cable, wouldn't hurt to try since the projector is 480p native.

This is a general response i posted to a similar question, but it is a simple fix that may apply to your hdmi cable.

Ok, here's the deal with monster cables. Sometimes i regret paying as much as i do for the cables, but the new line (1000 hd) are future proof by monster with a replacement guarantee, so i bought the 1000 hd cable at 35' to run from my hdmi swtich (i have four sources, a ps3 (1808p), an xbox 360 (1080p), an htpc (1080p), and an hd dvr (1080i)) to my 1080p projector. When i installed the first cable as indicated in the instructions by mc, with the arrow pointing toward the destination (my projector), there were the green lines you spoke about on all three of my 1080p sources. The 1080i picture from my hd dvr looked fine. I called mc and they said it was possibly a defective cable, so they sent me a replacement. I installed the replacement, same way, same thing, green lines on my 1080p sources, perfect picture from my 1080i hd dvr. I had a brain fart and turned the cable around, to where the arrow was pointing toward the source (the hdmi switch), and all four sources had perfect pictures. I called mc support and asked them why that would be, and they said that they've run into instances with some of their cables from a particular production run were shielded backwards, and thus the arrow goes in the wrong direction. Apparently the shielding is directional to help avoid interference. I told the rep that i thought that didn't speak highly of mc's quality control, and he claims it was an isolated instance. You may have also received a cable from a "bad" production run. And since a 1080i signal is less "complicated" and less prone to interference versus a 1080p signal, that explains why your ps3 (1080p) signal had a problem and not your wii (1080i) signal. Hope this helps somebody.