wify interference ?

[Jey123456]

For some weird reasons, the pandora seem to be producing quite a lot of wifi interferences, i just noticed today after feeling some major internet lags on my pc, while downloading on my pandora at 800-900kb/sec. So i did some tests, my wifi is b/g/n, i have a laptop that connect on 802.11g without any issues and download at 1.5-2mb / secs while not affecting the main computer whatsoever, but weirdly, if the pandora download at even 400-500kb / sec using wget and a source on my lan, every other wifi tool (iphone, 3 laptop and the 2 pc) start seeing an increase in the 800-900ms ping to the router.


The pandora is the only wifi device i own causing that issue. i hope it can be resolved with some drivers update, but otherwise, i guess ill have to buy a wifi dungle and use the usb port for my wifi needs, feel kindoff a waste considering there is an integrated one. If i had a bit more hardware knowledge, i would give it a go myself to fix it, but sadly, my programming knowledge doesnt extend that far ><.


Anyway, i still love my pandora, i just wanted to see if other peoples notice the same issues im having (i noticed on HF5 rc2 but might be older), hopefully someone able to fix it will be able to reproduce and work on it XD. If need be, i can be a guinea pig, i have a good knowledge of linux in general and aint scared of messing around my system.


P.S. Funny thing is while every other wifi device i own go crazy, the pandora itself stay stable at bellow 100ms (not what i would consider acceptable for a pc, but on an handeld device i can live with that).


In comparison, i can be transfering between my old laptop and main computer using wifi at 2 mb/sec while downloading from the web on the main computer at 3.5mb/sec and still get a ping lower than 2ms to the router, so i doubt its a wifi bandwith issue.

 

[kc187]

For some weird reasons, the pandora seem to be producing quite a lot of wifi interferences, i just noticed today after feeling some major internet lags on my pc, while downloading on my pandora at 800-900kb/sec. So i did some tests, my wifi is b/g/n, i have a laptop that connect on 802.11g without any issues and download at 1.5-2mb / secs while not affecting the main computer whatsoever, but weirdly, if the pandora download at even 400-500kb / sec using wget and a source on my lan, every other wifi tool (iphone, 3 laptop and the 2 pc) start seeing an increase in the 800-900ms ping to the router.


The pandora is the only wifi device i own causing that issue. i hope it can be resolved with some drivers update, but otherwise, i guess ill have to buy a wifi dungle and use the usb port for my wifi needs, feel kindoff a waste considering there is an integrated one. If i had a bit more hardware knowledge, i would give it a go myself to fix it, but sadly, my programming knowledge doesnt extend that far ><.


Anyway, i still love my pandora, i just wanted to see if other peoples notice the same issues im having (i noticed on HF5 rc2 but might be older), hopefully someone able to fix it will be able to reproduce and work on it XD. If need be, i can be a guinea pig, i have a good knowledge of linux in general and aint scared of messing around my system.


P.S. Funny thing is while every other wifi device i own go crazy, the pandora itself stay stable at bellow 100ms (not what i would consider acceptable for a pc, but on an handeld device i can live with that).


In comparison, i can be transfering between my old laptop and main computer using wifi at 2 mb/sec while downloading from the web on the main computer at 3.5mb/sec and still get a ping lower than 2ms to the router, so i doubt its a wifi bandwith issue.

Are you running any file sharing programs, like transmission? And what are you using as a reference for your ping?

 

[Jey123456]

nothing fancy for the ping. simply a ping -t 192.168.0.1 on the windows machine and ping 192.168.0.1 on the linux boxes. For the tests i had nothing other than the file transfers i started eating up bandwith, my issue is quite consistent too. No matter what i do on any other of my wifi connected device.


I can get a speed in the mb/sec (between my bigger laptop and main pc, which both use N, i can transfer at about 13megabytes/sec and can see an increase of ping in the 10-12ms during that time).


On the old laptop using 802.11 g, im able to get 2-3mb/sec transfer without any noticeable increase in ping delay (sometime it will spike at 2-3ms, but never higher).


If i start a transfer on the pandora from the internet, ill reach 900-1000kb/sec which is great for a mobile device, but during that transfer the ping on my 2 laptops and main computer go from <1-2ms to 800-900ms.


If i start a transfer on the pandora from my lan, ill reach 500-600kb/sec thats still nice, but i also see the same ping increase (chance are the difference in speed between lan and internet in that case, is caused by the fact my computer from which it download is close to losing the wifi while the pandora transfer).

 

[WizardStan]

Very strange that you're getting that. Two things I can think of: first, you might have a lot of interference on the channel to begin with, and the Pandora is just kind of the straw that broke the camel's back, as it were, and you could try some different channels on your router to see if that helps; or (far more likely) you're Pandora's wifi is super powered for some reason and you need to lower the power a little bit. Open a terminal and run

sudo iwconfig wlan0 txpower 10db

and see if that helps. 20db is the default, half power might work, but you may need to go up or down a few to figure it out.

 

[EvilDragon]

Hm, I remember that happened with an older WiFi firmware, pre-Hotfix 5.


What version are you running?

 

[Linux-SWAT]

I also noticed WiFi is strong. I have the ability to feel WiFi force in my body when i'm close to a device. I use ZaxxonHF5RC1.

 

[Jey123456]

im on hotfix5 rc2. and yea, i know about the power command, im using it at 1mW which is essentially 0 db. (i tried with 20db as well thinking it might be the cause).


I also tryed disabling my iphone and 2 laptop to see if the issue was still around. and yes it was , on the wifi there only was my main computer and the pandy, and the main computer ended up with 800-900ms during a pandora transfer.


i also tryed the channel possibility, right now im on channel 5 and am the only wifi network all my system can detect. i tried channel 1, 2, 7 and 11 with unfortunatly the same results.


On a similar note, running the txpower any higher than 0 cause my pandora to overheat and the network freeze a lot. with it at 20, i get a network freeze every 3-4minutes downloading at max speed. at 0, i get a freeze every 2hours more or less.

 

[WizardStan]

Your wifi chip sounds very, very powerful. I can't even begin to imagine what might be the cause or solution to your problem :blink:

 

[Jey123456]

i wish it was so powerfull that it could start fixing itself ! T_T. but it refuse and i doubt its something that will wear with time lol.


Oh well, i was in need of a 802.11 N wifi usb stick anyway, so guess ill go buy 1 tommorow and hope i can get it working on pandy, if i cant heh... ill go buy another model ! till i find one in store that i can get to work. (i hate waiting for delivery, the pandora took too long already !)

 

[metallurge]

It might be related to the size of the Pandora's antenna (smaller than your laptop's), and interference on the 802.11 channel you are using. I think I'd try changing channels on your wireless router/AP and see if that changes anything. I'd also try just rebooting the router/AP. Also, I have run into flaky wireless routers/APs here lately that simply don't work properly all of the time. One that I spent a loooooong time diagnosing had a broken DHCP server, such that it would hand out one address successfully, and then sometimes fail handing out the next ones, even over the wired connections. Good luck!

 

[Jey123456]

thx for the suggestion, tho as i said earlier, i already tryed a sweep on the channel range, also wouldnt smaller antena on the pandora cause the pandora itself to have an higher ping... and not every single other device BUT the pandora XD. during all those tests, my pandora still kept pinging in the 100ms while other systems went up in the 900ms.


As far as rebooting the router goes, i tryed that, hell.. i even tryed my 3 older routers just to see if it would work better on one of those. unfortunatly, the results were consistant, no matter which router or channel i used, i ended up with the same issue. as soon as the pandora start transfering anything higher than 200kb/sec, every other wifi device i own pretty much go crazy.

 

[metallurge]

wouldnt smaller antena on the pandora cause the pandora itself to have an higher ping... and not every single other device BUT the pandora XD.

Actually, I believe all 802.11 traffic shares the same bandwidth between all devices. Let's say your Pandora is at the fringes of reception for its antenna size. So, let's say that, instead of running at max 802.11g speed of 54 Mbit/s, it auto-negotiates itself all the way down to 6 Mbit/s, which is the minimum 802.11g. I strongly suspect that, if this happens, ping times for everybody on wireless go up. And, if you have a badly-implemented router, ping times for everyone on the network could go up as well.


The other scenario to contemplate is if you are in an area where 2.4 Ghz is congested (say, an apartment complex). The interference from everybody's cordless phones, wireless routers, badly-shielded microwaves, baby monitors, alarm system components, etc. could make the difference between a reasonably-reliable connection with a big-enough antenna like your notebook has, but with the smaller antenna in the Pandora, you don't have enough signal to reliably get over the background.


It does sound as though you have tried the things to attempt diagnosis, though. Perhaps it might be a good idea to take your Pandora somewhere else and see how it behaves in a different wireless environment?


I don't know how easy it is to get to the place where the antenna wire connects to the motherboard on the Pandora, but I think I might also inspect that connection and see if there is anything loose or damaged there. I'm assuming there is an antenna wire that goes through the hinge along with the LCD cable up into the screen like on most laptops, anyway...


Of course, you could also try eliminating software issues by temporarily disabling WEP/WAP encryption and see if that makes any difference. But I'm guessing that others would be having these issues if it were that simple.


I'd be sure to try it unplugged from the charger as well, just in case you are picking up noise from the power supply.


I'd disable any router-vendor-specific 802.11 "speed boost" type stuff.


I'd consider configuring the router for 802.11g only (not b+g), and if that doesn't work, 802.11b only. 802.11b is more immune to interference, by the way.


If you do an "ifconfig wlan0" (or whatever the Pandora equivalent is), do you see collisions or errors after you have been connected for a while?


Once you saturate the wifi with devices/transfers/activities, performance is likely to suddenly fall off a cliff. You'll be spending all your time retrying packets. That does sound rather like what you are seeing. It's like when your linux box exhausts RAM and it starts swapping.


That's all I've got at the moment...


Good luck!