WiFi experience feels painfully slow with cellular data enabled

[TK2011]

A new unlocked 950 dual sim owner here. After struggling with randomly slow content loading experience across all apps over WiFi, I've discovered that it only happens with cellular data enabled. If I turn it off, WiFi and all apps work fast as you would expect with a good WiFi signal at home. Anyone else with this issue? Problem doesn't necessarily show up in network throughput tests because the slowness appears to be due to a kink in TCP/IP connection establishment stage (e.g. DNS lookup), not payload transfer stage. I think the OS has a bug in the networking stack when both WiFi and cellular data are enabled. Other things to note: I'm using AirVoice (AT&T MVNO) microSIM cut into nanoSIM. SMS and MMS work fine after programming the SIM settings but I wonder if OS expects a nanoSIM with built-in network settings... Ordered a proper nanoSIM from Airvoice to test this. My wife's 950XL with proper AT&T nanaSIM doesn't have this issue and it FLIES on WiFi with or without cellular data enabled.

 

[Tepid]

I will just got out on a limb and say it's the SIM causing the issue.





My wife and I, both have the 950, not dual SIM, and not unlocked, on ATT. No issues with WiFi at all.

 

[TK2011]

Yeah, it may be related to the converted SIM. Can't wait to try out the new SIM in a few days. Other than this issue phone performs exceptionally well especially with W10M optimized apps.

 

[Stanleywinston]

There's a long thread on Ms support about problems with WiFi. It's so old and long now that it's not really worth reading but there does seem to be some people complaining that dual sims are an issue. Also some people that Bluetooth is the issue and some that 4g is the issue! It's probably all different issues! I was having loads of WiFi issues until the newer Redstone builds so I think help is coming to the productions builds

 

[campbellc]

I have a 950 on AT&T and my wifi os terrible. Regardless of whether or not my cellular connection is or off. I constantly am dropping my wifi connection, slow speeds etc. I have been going over my carrier data limit almost every month since I have had this phone.

 

[ankit360]

A new unlocked 950 dual sim owner here. After struggling with randomly slow content loading experience across all apps over WiFi, I've discovered that it only happens with cellular data enabled. If I turn it off, WiFi and all apps work fast as you would expect with a good WiFi signal at home. Anyone else with this issue? Problem doesn't necessarily show up in network throughput tests because the slowness appears to be due to a kink in TCP/IP connection establishment stage (e.g. DNS lookup), not payload transfer stage. I think the OS has a bug in the networking stack when both WiFi and cellular data are enabled. Other things to note: I'm using AirVoice (AT&T MVNO) microSIM cut into nanoSIM. SMS and MMS work fine after programming the SIM settings but I wonder if OS expects a nanoSIM with built-in network settings... Ordered a proper nanoSIM from Airvoice to test this. My wife's 950XL with proper AT&T nanaSIM doesn't have this issue and it FLIES on WiFi with or without cellular data enabled.

Before reporting any issue . Plz update ur firmware and OS

 

[TK2011]

I have a 950 on AT&T and my wifi os terrible. Regardless of whether or not my cellular connection is or off. I constantly am dropping my wifi connection, slow speeds etc. I have been going over my carrier data limit almost every month since I have had this phone.

You might want to try another router. I experienced a problem just like that (a different issue than the one in my OP) with Linksys EA4500 which I remember had a compatibility issue with another device I used to own. Bought a cheap D-link and no problem so far except when I turn on cellular data which I think is a networking bug in W10M.

 

[TK2011]

My real nano SIM from Airvoice arrived but the slow WiFI issue with cellular data enabled still persists. One thing I notice (before and still now) is that the SIM menu detects my sim and ask you to choose a 'profile' between "AT&T" and "Straighttalk" which do not apply to me (tried both to no avail). Also, APN sign-in type value (PAP) don't seem to stick after configuration... Something's not right in the OS even though txt, cellular data and picture messaging all work okay. I could just turn off cellular data when using WiFi but then I can't receive picture messaging (or group txt which uses MMS/cellular data) during that time so it's not a good workaround.

 

[TK2011]

Before reporting any issue . Plz update ur firmware and OS

I am running the latest release preview .338 with the latest firmware for my HW. I might try the Redstone build later.

 

[TK2011]

Yay, the latest Redstone fast ring build fixes this issue!
That's the 14356 build if anyone's tracking this problem. The slow ring doesn't do it.
Coming from the Threshold branch, I'm seeing a few new things here and there, mostly positive. Windows Central app is the only one not working after the update. LOL

 

[Vasrias]

If apps don't start try restarting the phone or reinstalling the apps.

 

[TK2011]

Crap, problem came back after upgrading to 14361 this morning.

 

[TK2011]

This has become a solo journal, lol, but I found out to my pleasant surprise that W10M no longer needs cellular data connection enabled by user in order to receive/send picture (and group texts) properly. This was confirmed on both my 950 DS on 14361 and wife's 950XL DS on production build. If I recall correctly, my 920 (sold to Ebayer) running WP8.1 and possibly also early version of Threshold W10M did require cellular data in the past so this must be a new hidden feature MS added. Now, I'm not saying OS doesn't use cellular data connection at all for MMS, it may very well be using it but perhaps does it in background and doesn't require explicit enablement by user. All this makes sense if you think about it. May also explain why we are seeing bugs like the one in this thread if they've been tweaking the related code. Ultimately, this new finding makes the bug much more tolerable because I can just keep cellular data disabled without worrying about missing picture/group texts. Hope this info helps anyone having the same problem.