iMac Wi-Fi Issues

[SkyRaider]

Basically, at Home, I have a solid 30mbps connection speed, almost every device I have confirms this. My iMac (Late 2012, 27") however, disagrees. It refuses to connect to the WiFi at any speed above 4mbps, which although this is bearable, it has a ridiculous latency when trying to load anything, so trying to do anything such as streaming, online gaming, etc just becomes difficult.

I really can't seem to find any cause of this issue. Heres a list of actions I've taken so far:
- Turned Bluetooth Off and used Wired Keyboard & Mouse. (Nothing Changed)
- Disconnected External HDDs. (Nothing Changed)
- Tried Wired Connection (Worked, but not practical for me)
- Moved any possible causes of interference away from the iMac. (Nothing Changed)
- Booted off the iMac HDD using my MacBook Pro over Firewire. (Was able to get the right speeds)
- Also booted off Laptop SSD over Firewire using my iMac. (Issue was persistent)
- Restored from old Backup before issues occurred. (still occurring)
- Tested in Safe Mode (Still Slow)
- Ran Apple Hardware Test (Passed)
- Moved iMac to another desk. (Still no luck)

I am starting to run low on ideas, I really don't want to return this iMac, as I'd prefer not to have to go through all the hassle, especially as everything else is fine.

Note: For a short while whilst attempting to fix it, I was able to achieve the right speeds but it disappeared again after a few mins.

Im hoping someone here will have more experience of dealing with these issues,
Thanks in Advance
Andy

 

[mikeqls]

hi...im no expert..... but i had similar issues with pc - wifi works fine with all other devices - Ipad, three iphones, and 2 iPods.... it just would cut out from pc intermittently..was driving me mad - apple care said i had faulty wi-fi card and to take machine into store - didnt fancy that as only had it 3 months!! further calls and more so called experts - someone suggested the ethernet cable direct to machine.... something to do with frequency of other devices may effect pc - wireless home phones also in room....

So a quick investment of an ethernet cable ( much easier than a trip to local store!!) - since connecting with ethernet had no issues at at all...all worked perfectly - been about two weeks now so am pleased...... one guy suggested getting a different router....as BT aren't known for supplying the best....but as it is all ok at the moment....i reluctant to touch it!!!

it isn't broke - so i wont fix it!! lol

hope that helps!!
Mike

 

[SkyRaider]

Hiya mikeqls, thanks for replying. I was really hoping it wasn't a hardware issue, I love this new computer and don't want to return it

I would prefer to use a wired connection, unfortunately, theres only 1 router, and thats in another room connected to another computer, so that option isn't ideal. I managed to get it working using my MacBook Pros WiFi shared over Ethernet, but that isn't viable as a long term option. I guess if things are desperate, I could invest in a USB WiFi Adapter, I believe some work on Mac.

Although, not sure why, but today the issue appears to have fixed itself, not sure how, nothings changed since last night, but it could still return.

 

[mikeqls]

i felt the same..... i didn't want to return this one either....i think they must sense it..LOL mines ok now after it was threatened to go back to the store - seems yours has done the same!!

they got minds of their own!!! LOL

 

[bmcgrath]

Have you tried changing the channels on the router? How many other routers are in the area?

 

[justperry]

Hiya mikeqls, thanks for replying. I was really hoping it wasn't a hardware issue, I love this new computer and don't want to return it

I would prefer to use a wired connection, unfortunately, theres only 1 router, and thats in another room connected to another computer, so that option isn't ideal. I managed to get it working using my MacBook Pros WiFi shared over Ethernet, but that isn't viable as a long term option. I guess if things are desperate, I could invest in a USB WiFi Adapter, I believe some work on Mac.

Although, not sure why, but today the issue appears to have fixed itself, not sure how, nothings changed since last night, but it could still return.

If it gets back again you should try it in a friends or families place, you might have interference inside your place.
Try for a few hours, if all is OK it's your place, if it still has issues it is most likely hardware related.
Wifi is one of Apple's weaker areas.

 

[SkyRaider]

Update: I believe I may have narrowed it down to interference, the issue seems to keep coming and going, I also had the same issue on my MacBook Pro the other day.

Does anyone know the best way of identifying the cause of the interference, considering I don't have access to all the computers in the house?

Andy

 

[Nuke61]

If you can move the wifi router, turn it 90* and elevate it. Use a wifi analyzer to get signal strength and channel crowding info. I have an Android phone and use an app called WiFi Analyzer that shows me signal strength as I walk around the house, and shows signal strength on the various channels. Do something similar either with an wifi analyzer and either your phone or someone else's.

 

[bmcgrath]

Interference can be caused by many sources:
- Microwaves
- Fridges
- TV's
- Wireless keyboard & mice
- Other wifi routers

If you do a quick google for wifi apps for Mac there's plenty which will tell you what channels other devices are on and you can then select a channel that's not so clogged up.