Wifi drops randomly, only this computer

[smirk]

Hi, I have a late-2013 MacBook Pro 15" that randomly drops its wifi connection. When this happens, the wifi icon in the menu bar shows that it is connected, but I'm unable to reach any websites and I'm unable to reach any other computers inside my network. When this happens, the only way to get things going again is to turn wifi off and back on again. The MacBook is in the same room as the router, and connects over 802.11N, 2.4 GHz.

Sometimes it works all day, sometimes (like today), the connection drops out 10 times during the day. I'm not aware of any other devices (iPad, iPhone, or a PC laptop) having this problem. I also don't see any obvious log entries in the router (OpenWRT) that would indicate a problem, but I'm no expert at reading those things.

Following a post here, I've tried creating a new network location and setting its MTU to 1453, but it didn't seem to help. Updating from El Cap to Sierra didn't help, either.

Connecting the laptop to ethernet results in a stable connection, but I'd rather use Wifi.

Any ideas of what to do to resolve this? Is this a known issue with the MBP? Could it be an incompatibility between the MacBook and the router?

Thanks!

 

[jerryk]

Does it work OK in other locations?

If not, it might be that the antenna connection is loose, or the wifi module is loose or failing.

 

[smirk]

It seems to work at other wifi locations, although I've never used it for an extended period of time outside the house. I guess I could go to Starbucks and hang out for a few hours. I've used it an the office a handful of times for several hours each time and it never dropped.

 

[jerryk]

It seems to work at other wifi locations, although I've never used it for an extended period of time outside the house. I guess I could go to Starbucks and hang out for a few hours. I've used it an the office a handful of times for several hours each time and it never dropped.

If that is the case, then it must be something in the Wifi at home. Is this a new problem? Did you install an update to OpenWRT?

 

[ZapNZs]

Have you ruled out the probability of interference? (power lines, other 2.4 GHz Wifi signals, USB 3, microwaves, 2.4 GHz phones or Bluetooth, etc.)
Have you tested using a different channel or 5 GHz (if the router is capable of it)?
If this was an issue relating to the MTU setting, wouldn't that also affect ethernet as well as Wifi? (provided you are plugging into the same router that you get the signal from)?

 

[smirk]

Have you ruled out the probability of interference?
Have you tested using a different channel or 5 GHz (if the router is capable of it)?
If this was an issue relating to the MTU setting, wouldn't that also affect ethernet as well as Wifi?

To be honest, I didn't really know what I was doing with the MTU setting; I just tried something that someone said worked for them.

I suppose it could be interference, but no other devices or computers have this issue, so I don't know.

I have changed wifi channels, with no effect.

One thing of interest is that it happened again a few minutes ago and I spent some time investigating it. So Ping worked, and Mail.app was able to download IMAP email from my ISP! It was not able to download email from Gmail, though. No websites worked, and the command line program Curl wasn't able to connect, either. Remote desktop to a Windows PC on my network failed.

Does that make any sense?

 

[jerryk]

To be honest, I didn't really know what I was doing with the MTU setting; I just tried something that someone said worked for them.

I suppose it could be interference, but no other devices or computers have this issue, so I don't know.

I have changed wifi channels, with no effect.

One thing of interest is that it happened again a few minutes ago and I spent some time investigating it. So Ping worked, and Mail.app was able to download IMAP email from my ISP! It was not able to download email from Gmail, though. No websites worked, and the command line program Curl wasn't able to connect, either. Remote desktop to a Windows PC on my network failed.

Does that make any sense?

Very strange behavior. Try resetting the MTU to automatic to get back to a known state.

And if you have another router/access point give that a try.

 

[Fishrrman]

"So Ping worked, and Mail.app was able to download IMAP email from my ISP! It was not able to download email from Gmail, though."

Instead of a "wifi" problem, could this be a DNS-related problem?

 

[smirk]

Instead of a "wifi" problem, could this be a DNS-related problem?

That's what I thought, so I pinged 'www.apple.com' to get its IP address, then tried connecting to that (with both web browser and Curl), but neither worked.

I also went into Network settings and changed the DNS to Google's DNS address, but that didn't work.

A friend of mine had a similar problem with his MacBook, and he said that replacing his network switch resolved the problem. I do have a switch, but I don't see how it would come into play since the MBP connects to the router via wifi, and the router is directly connected to the cable modem.

I hate to do this, but perhaps I should buy a new router and hope that solves the problem. To be honest, I thought this was a widespread issue with MacBook Pros, for some reason.

 

[Sanpete]

Your ISP might be able to provide some additional help. Maybe they have some ideas about why you could do some things over the internet but not others.

 

[jerryk]

That's what I thought, so I pinged 'www.apple.com' to get its IP address, then tried connecting to that (with both web browser and Curl), but neither worked.

I also went into Network settings and changed the DNS to Google's DNS address, but that didn't work.

A friend of mine had a similar problem with his MacBook, and he said that replacing his network switch resolved the problem. I do have a switch, but I don't see how it would come into play since the MBP connects to the router via wifi, and the router is directly connected to the cable modem.

I hate to do this, but perhaps I should buy a new router and hope that solves the problem. To be honest, I thought this was a widespread issue with MacBook Pros, for some reason.

I have never heard of any widespread issue with wifi on the MBPs. But combo routers with wifi are a pretty stressed unit. They are doing router/firewall/switch/access point, all in one package.

After killing a number of them over the years, I have given up on these combined units. I now have a router box that does routing and firewall, dedicated switch boxes, and wireless Access Points powered via POE from the switches. This has dramatically improved my performance and reliability on both wired and wireless connections.

 

[SSD-GUY]

I have had this problem with quite a few late 2013 Apple laptops (MacBook Air 11, MacBook Air 13 and I think even my late 2013 rMBP 13).

What fixed it was getting the WiFi card replaced by Apple.

I think what happens is that the wifi card gets overwhelmed. Try this, go to the App store and download OS X El Capitan or Sierra (Don't install it, just download it)

Download it a few times and I can almost bet that you wifi will 'time out' again even though it will remain connected.

Give it a try.

 

[smirk]

I think what happens is that the wifi card gets overwhelmed. Try this, go to the App store and download OS X El Capitan or Sierra (Don't install it, just download it)

Whoah, seriously? Perhaps an even better test would be transferring a multi-GB file over wifi from another computer. That should completely saturate the wifi.

How many wifi cards have you had replaced?

 

[SSD-GUY]

Whoah, seriously? Perhaps an even better test would be transferring a multi-GB file over wifi from another computer. That should completely saturate the wifi.

How many wifi cards have you had replaced?

Yeah give that a try and see if yours starts playing up.

I've changed it on the 13 MBA and it solved the issue. I can't remember whether I changed it on the 11 MBA, I think I did and it solved the problem, and the 13 rMBP I 'upgraded' to a 12 rMB.

 

[smirk]

The plot thickens.

I did a bandwidth test like @SSD-GUY suggested, by copying a 20 GB file from my home server to the desktop. It was chugging away for probably 10 minutes (it's only 802.11n) and then I launched Chrome, and its many tabs started to load. Within 20 seconds, the wifi dropped. Ok, that's interesting. So then I repeated the test, with the exact same results!

Not sure how to interpret this. Something in my router can't handle all those simultaneous connections? Or the MacBook's wifi card? Or...?

 

[SSD-GUY]

The plot thickens.

I did a bandwidth test like @SSD-GUY suggested, by copying a 20 GB file from my home server to the desktop. It was chugging away for probably 10 minutes (it's only 802.11n) and then I launched Chrome, and its many tabs started to load. Within 20 seconds, the wifi dropped. Ok, that's interesting. So then I repeated the test, with the exact same results!

Not sure how to interpret this. Something in my router can't handle all those simultaneous connections? Or the MacBook's wifi card? Or...?

Trust me, it's the WiFi card. I had the exact same problem at my home router, my University wifi connection etc.

Apple won't admit it but they obviously had a bad batch of WiFi cards.

 

[smirk]

Just wanted to give an update. I replaced the router with a new one, and it has been a week now with no wifi drops. I'm very relieved it wasn't the wifi card in the MacBook!

Thanks, everybody, for all the advice.

 

[jerryk]

Just wanted to give an update. I replaced the router with a new one, and it has been a week now with no wifi drops. I'm very relieved it wasn't the wifi card in the MacBook!

Thanks, everybody, for all the advice.

Yep. These combo access point-router-switches are doing a lot. They die after a while.