issue with minidisplay adapter and wifi

Chiming in to say that I am experiencing this problem as well. I have the Apple DVI displayport adapter and whenever I plug it in I lose my wifi connection, and my connection returns to normal when I unplug the adapter. Same thing occurs in Windows XP. I also am unable to change the channel of my wireless access point so hopefully another workaround materializes soon.

Since I spent about $300 on AppleCare, I am using the first party connector, and this problem just frankly shouldn't be happening, I decided to call an Apple Expert to have them try and fix the problem. After spending over an hour with them on the phone trying to find a work around, I have been directed to set up an appointment at an Apple Store to try and see if a solution can be found there. Basically the technician, who was actually a supervisor after the first Expert couldn't find a solution, said that we have tried every possible option software-wise and this is definitely a hardware issue. The Experts were very nice and thoughtful, no complaints about Apple tech support in general, it is the best I have had an experience with.

Anyway, the two possible conclusions I can come to regarding this problem are this:

1. The DVI DisplayPort adapter or the MacBook Pro DisplayPort hardware specifically or MacBook Pro hardware in general are not FCC compliant and interfere with the wireless signal and the Airport connection. IE, the interference could be coming from just outside the computer or internally.

2. My MacBook Pro is defective, and some mid-2009 MacBook Pros do not experience any difficulties with the DisplayPort their Airport connection.

I will be heading into the Apple Store sometime next week to see if I can get this problem resolved. Wish me luck! I will forward any resolutions along.

Greetings all, I have the same issue and changing the Airport Network channel #'s (from automatic to 11 then 6) and trying to realign the mini display adaptor cords have not worked. What I fine really strange is:

• The network (Airport Extreme base station an Airport Express, supporting three Macs, streaming music, Direct TV On Demand connected, shared printer, etc) worked perfectly for the last nine months
• Running 10.5.8 on all machines (no OS change on any machine)
• No hardware changes

Then about 3 weeks ago the MacBook (only when connected to the HDMI cable) drops the connection. The only conclusion I can reach is that some recent software update must be causing it...anyway I thought this info might be of some help. Calling Applecare now and will post anything helpful.

Message was edited by: digitalmem

Update:

- In the earlier post I accidently wrote, "only when connected to the HDMI cable" and I meant the "mini DVI adaptor cable."

- I also tried the network on channel 1 then on 5 and neither worked

- Based on an earlier post I also tried setting the network to only 802.11n which is supposed to operate in the 5GHz range instead of 2.4 unfortunately that didn't work either

Called AppleCare and:
A.) Thought it was really weird and had no mini display port/adaptor interference issues logged

B.) Based on everything I had already tried they recommended I take the display and laptop into the Apple Store were they can verify the issue on their network (yeah, not convenient but at least the store is close).

I'm booking an appointment now and will post and update when everything is fixed (hey, you got to be optimistic).

Any updates on your visit to the apple store?

I am having this same problem with a brand new Macbook Pro 15" 2.53 Ghz that I bought earlier this month.

I am unable to control the channel of my WiFi access point, but I found that it was already running on channel 1. So changing the channel is not a fix for me.

Should I be trying to buy an original apple Mini DP to HDMI adapter? I am currently using a 3rd party adapter. I am finding that if I place my palm around the adapter and shield it then the WiFi throughput improves.

Is this a H/W problem that Apple can fix? If so I should try to take it in before my 90 day warranty expires. Could one of you that has gotten this problem fixed by Apple please let the rest of us know how they fixed it and whether it is a H/W or S/W problem.

there was an airport update sometime around early December and noticed ever since then the problem had corrected itself well atleast for me that is, see if you have a pending airport update and see if it works, my two cents.

I have the 15" 2.66 GHz MacBook Pro, bought last week with the expensive DVI adapter, and I have the same problem. It says my hardware is up to date. I also can't change channels on my wireless router 😟

Has anyone actually managed to get anything useful out of the apple team to fix this? Or will I need to disconnect my monitor each time I want to go online?

What sort of wireless router do you have and how are you going about trying to change it, SydneyKiwi?

If you aren't using an airport router it is probably simply a matter of accessing it through your web browser and following the instructions in the router manual .

I should add that it would be very helpful if those experiencing this problem could mention which particular monitor they are trying to connect to in their posts. Sounds like some may have an RF suppression issue of some sort to me. I have no probs at all with wifi on two different networks while connecting to either an ACER or BenQ monitor, using the Apple minidisplay adaptor. The problem may even relate to something as simple as a cheap, badly shielded, monitor cable. More information from the "sufferers" would make it much easier to suggest meaningful solutions. At least the level of information provided by "tele-player" above would come in handy!

Cheers

Rod

Thank you for planting the seed of trying a different cable. I swapped DVI cables for another that was seemingly the same gauge as the one that came with my monitor and immediately network performance (per ping) improved. I believe you may be on to something with the shielding suspicion.

I'm using a 24" LG Flatron W2452T monitor. The DVI cable that shipped with it gave me more trouble on this issue than another I had laying around (don't know the source, sorry).

I now have this problem where the only thing that changed was the model of my MacBook pro (and the OS version)

I was recently upgraded from a vintage late-2007 MacBook Pro (OS X 10.4) to a late-2009 MacBook Pro, new design, unified body (OS X 10.5.8). On the old model the DVI connector from my 20in Dell display (2405FPW, 1920 x 1200 @ 60 Hz) plugged right into the notebook and the WiFi (airport) was fine. On the new model I had to buy a mini-display port to DVI adaptor, and the wifi is not fine. Nothing else changed, the new notebook sits in exactly the same location as the older one.

I see the same symptoms as reported above. When the display is not connected, my wifi is fine; when the display is connected, the wifi fails. Note that the display itself behaves just fine.

I used iStumbler (release 98) to get some readings of signal and noise level. The signal is typically 69 - 71% regardless of configuration. When the display is not connected the noise is typically 11%.

Connecting things to the notebook:

When the display is connected via the mini-display adaptor and its power switched on, the noise jumps to 22 - 25%, occasionally 30%. (And of course, wifi fails.)

Connecting the notebook power cord does not affect the noise level or wifi.

Connecting a usb hub adds 4 or 5%, but wifi is OK.

Moving things around on the desk can affect the noise level (and signal) somewhat (maybe 5%), but not predictably. What is predictable is that connecting the DVI display almost always breaks the wifi connection.

Note: by 'break' I mean that connections to the internet time out. Even so, in System Preferences, the OS still believes it is connected and shows its IP address etc. But, if I turn the airport off and then back on, it is usually unable to reconnect to the access point (all this while display is still connected) .

A blight on my otherwise wonderful MacBook Pro....

-C

PS: originally posted this message as a reply to a Display thread, but this isn't a problem about the display; it's about the WiFi.