major screen flicker when using kvm

interesting, just checked it and it does not matter - but not a bad idea tho. ground buzzes with audio are quite common and who knows, maybe the video suffers the same interference.

with respect to the issues i've been having though, no - having the plugs grounded or not or on battery vs ac makes no difference.

thanks tho!
-dave

update:
ok, so i purchased another mini displayport to DVI adaptor just to test to see if perhaps i got a bad one...no such luck.

i did discover something tho.

i shut down the machine and unplugged the displayport adaptor, then plugged it back in.

if i power up the macbook pro with the focus of the switch to that machine...so that the monitor is recognized upon boot up, everything seems okay.

using it then for a few hours i saw the symptom return only slightly, but certainly nothing like how it was behaving earlier. a quick reboot and all is fine again.

so if you're having these issues, try first shutting down and unplugging the adaptor. plug everything in and boot back up making sure the kvm focus is targeted to your macbook pro.

until something else works, this is as good as anything. 🙂
-cya

ya, it's interesing - it can go for hours without a glith, then it goes crazy. i've now resorted to just unplugging the monitor from the macbook pro, letting it (the monitor) auto-shutoff then plug the macbook back in.

it seems to work for a while but a totally ghetto fix...geezzz.

i sure hope a software update comes out to address a potential digital sync problem. that might be what it is, but who knows. unless a lot of other people who are also experiencing the same problems come forward, i feel as tho we'll be out there twisting in the wind.

keep this thread open tho just in case you or someone else discovers what's actually causing the problem.

cya,
-dave

hi jrsmobile,

ya, i've certainly tried that...doesn't help.

the only thing i've found to help at this point is when it starts to glitch, i'll just unplug the mini displayport adaptor from my macbook pro - let the primary screen focus over to the macbook pro, then plug it back in.

after that, i'm cool again for a period of time...might be hours, might be minutes.

hehe - it's a real professional look too...**leans over desk in front of client to unplug and replug monitor.

i'd like to say also, i've seen threads and posts elsewhere describing a similar problem with the mac pros - but it's not the same effect. there, the pixels often follow an edge of whatever happens to be on the screen - like a green or blue row of bright pixels marching along an edge of a circle for example. that effect really looks like the result of an overclocked video card (which i've seen a LOT of in my quake 3 days on my pc!).

when my screen glitchs, it looks like the cable or connection is loose - and also there is a pixel, snow effect (noticeable on a black background). to my untrained eye, it looks like a sync issue.

anyway, here's hoping we get a fix!
-dave

i'd say it probably is - but what that glitch is, hard to say. is it the adaptor? is it the output itself? is it a driver issue? maybe it's a chipset incompatibility.

here's what i've done until this works out because i need to use one monitor for all 4 machines and i can't keep unplugging and replugging.

hard to explain but i bought another kvm, the belkin flip - i use that on the macbook only and it works great.

in more detail, i have the iogear 4 port plugged in and controlling the other 3 machines. the monitor output of that switch now goes into one side of that belkin flip - the other side goes to my macbook pro. then of course, the flip gets plugged into the monitor. the only thing i use from the 4 port switch is the usb functionality, i just unplugged the monitor cable.

so...how it all works is, i just switch to the port on my 4 port to which my macbook is connected like normal, but to switch to the video, i just hit the little button that comes with the flip. to switch back, i just flip the flip back to the 4 port iogear and i'm back to controlling the other machines.

why did i choose to do it this way? well, to experiment with buying other kvm switches at $300 a pop was not something i was really into doing. most people were suggesting i try the gefen kvm, but that sucker weighs in at almost $700. also, part of me just didn't want to buy another 4 port just because one of the 4 machines didn't work with it.

my solution cost about $100 and for the time being, i'm totally glitch free.

i can post a you tube video better explaining my setup if you'd also like to try it, hopefully i explained it okay.

i'll keep checking here and hopefully in the next software update our problems will get addressed.

cya!
-dave

i've noticed no dimming as you've described, but the connection seems flaky so anything is possible.

robert, i've tried a second dvi adaptor and it didn't work for me.

i wonder if it's an iogear incompatibility? do all you guys having this problem also have the iogear?

-dave