Humming sound and speaker noise Beovision 7-40 MK IV

18 replies

moxxey wrote:

BTW, I'm sure I contributed to this discussion saying that I heard hissing through my BL9s connected to the MKIV. Where are those posts?

I also remember that Moxxey. But I think we have run across a few posts on fairly the same subjects.

I spoke to my dealer today, who has replaced a previous dealer now shut down where I bought my BL 9's. Current dealer says: Previous dealer known for using unoriginal cables to save a few bucks, and this is a known issue with those cables.

So... not to fire up the old cable discussion again, but that was what he said. I myself was unaware that I probably have unoriginal cables, but I most certainly will swap them as new dealer meant that was all it took. Can not say of course if you might have some odd fellow connected to your speakers, but I will at least give it a shot to switch.

takktakk wrote:

Can not say of course if you might have some odd fellow connected to your speakers, but I will at least give it a shot to switch.

Yep, could be the solution. Problem is that the dealer has glued them to my skirting (bottom of wall) 😮 Still won't explain why the slight buzzing was on the MKIV but not the MKIII in the same setup?

moxxey wrote:

takktakk wrote:

Can not say of course if you might have some odd fellow connected to your speakers, but I will at least give it a shot to switch.

Yep, could be the solution. Problem is that the dealer has glued them to my skirting (bottom of wall) 😮 Still won't explain why the slight buzzing was on the MKIV but not the MKIII in the same setup?

Well... I guess one could argue that the MK IV is for some reason somewhat different in it's setup? In many ways we would expect it to be. And that such a difference in some way made it more sensitive to what cables are in use...?

Of course that's snapped out of the dark night by me, but it provides a comforting peace of mind for now.... 😁

Hi,

I too have a new MKIV attached to a mac mini and so when I use the TV as a monitor (with no audio) the humming sound is certainly there and is annoying.  I read in a previous post that it might be worse when the TV is hung off the wall.  I am still undecided about whether to complain to my dealer.

David

d4vidl4ur4 wrote:

Hi,

I too have a new MKIV attached to a mac mini and so when I use the TV as a monitor (with no audio) the humming sound is certainly there and is annoying.  I read in a previous post that it might be worse when the TV is hung off the wall.  I am still undecided about whether to complain to my dealer.

David

My dealer has now brought this in as a major issue, with bno and await their response. I will keep you all posted on events. 

One more thing as I am going on anyway: As some of you may know there is an issue with the MK IV where it displays 50 HZ output on Signal Information during tv and 48 on BluRay which is exactly half of what it should be. Latest from bno on this: The panel is a 100 HZ panel, and would not even be able to display a 50 HZ picture. The information in the Signal Output field is wrong (output is 100 HZ) and the latest software fixes this bug.

Hi all

Just to let you know

I have the humming noise aswell, but only when turning on appletv connected through HDMI. Does anyone know if the latest firmware solved this problem??

Hi Moxxey

I just wonder if your replacement MK IV is better than the first one ? You mentioned that the sound delay is still there, but what about hummingnoise, and the other things you mentioned earlier?

Humming noise is still there. However, it's so quiet - and I sit quite far from the TV - it's acceptable for me. Besides, I only notice it if I switch to the PS3 and I've forgotten to switch the PS3 on (as an example).

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