Denon AVRX2400 Receiver adding blue noise to image - as per video...any suggestions? :-(

[jimster99]

So my Denon receiver (AVRX2400) has had its HDMI board replaced by Denon which fixed the defective "HDMI Input 3" issue I previously posted about. HOWEVER the other problem I was having (blue noise often being inserted into the image) remains. I've finally filmed it happening and uploaded a video to youtube - any suggestions as to what might be causing this and how can I get it fixed?

Here's the link:

As you can see, the Denon receiver intermittently adds "blue noise" to the image sent to the TV. This happens about 1/3rd of the time. It happens on all inputs and is not an HDMI cable/satellite box/TV issue (the same set up works perfectly with no blue image noise being added if you remove the Denon receiver from the pathway and simply plug the satellite box directly into the TV with the same cables or if you replace the Denon receiver with a different HDMI switch box). Sometimes the TV also displays an "invalid format" error message but this is infrequent and I haven't caught it on video yet.

I've used the Denon receiver's built in trouble shooting feature to reduce the maximum image quality to 1080p maximum (since the HDMI cables aren't 4k compliant and I don't use any 4k hardware anyway) and I've turned off the ancillary features like HDR etc again using the Denon. I've also used the Denon receiver to test the cables (and they were tested good on 1080p but failed 4k, which is fine since I don't use 4k anyway).

The really annoying thing is, I can (as demonstrated on the video) temporarily fix the issue by unplugging and reinserting the HDMI cable between the Denon and the TV and then it works for a period (sometimes a few minutes, sometimes a few days).

Turning everything off and on repeatedly also sometimes works but is much less predictable.

This is becoming really annoying and I'm on the verge on insisting on a replacement receiver, but I'd prefer to avoid doing this if it's at all possible. So you guys are my last chance! Any tips / suggestions / ideas??

Thanks!!

 

[Deleted member 39241]

I know it sounds illogical, but intermittent blinking issues like that are usually HDMI cable related. It could be the cable going from the source to the AVR or from the AVR to the TV that is the issue. The same cables may work perfectly well elsewhere, but for some reason, just not work properly between certain pieces of equipment.

A 4K certified cable, or maybe two, would prove the issue. Maybe buy a couple to try, they don't have to cost much:

https://www.amazon.co.uk/Omars-Cabl...514459&sr=8-3&keywords=premium+certified+hdmi

 

[jimster99]

Thanks! But there is no intermittent blinking issue - I'm changing the channel using the remote which is why it keeps going blank on the video - sorry if that wasn't clear (the reason I do that is that the blue noise image is even more obvious when you change channel).

The problem I'm having is that the image is having blue noise added to it by the Denon receiver. I'm pretty sure that's not a cable issue as I've tried it with every cable I have (including a *very* high quality 4k certified one).

 

[Hemiram]

You need to contact Denon and send that video to them and let them fix it. Looking at the guts of that receiver, I would expect it to have problems, given the transformer is under a circuit board, and that's a huge red flag. Nothing but air should be over a transformer whenever possible. Adding a fan would help, but Denon should know better, and it's not like an AVR is something that needs to be shrunk down making space limited, it's just bad design. I've been messing with electronics since I was a little kid and I learned a long time ago not to put any kind of heat sensitive components over a transformer. I've had radios and amps where the power supply area has almost no ventilation and the heat cooks the regulator ICs, the caps in the area, and in the case of the Icom R71a, HF receiver, the PC board itself, getting so hot solder deteriorates! Most of the radios can be run on a 12V power supply, solving the problem, but amps and AVRs can't easily be. I helped a friend move the PS on an old amp to a separate box, with an umbilical over to where the PS used to be. Dropped the temp on both the PS and the amp a lot, even without the fan we planned to add.

Good luck!