Dota 2 lag spikes

[#1]

I've brought this up with the support centre team to no avail, so I figured I'd try my luck here incase anyone here knows anything that they might not.
I've been experiencing network lag spikes and stutters when playing dota 2, especially if I have a VoIP program running at the same time as playing. It doesn't seem to matter what time I play, it's always just as bad. I haven't known for this problem to happen with any other multiplayer game that I play, but I have to admit that I don't play many other games.
My ping is always very low in-game, so it's just spikes rather than constantly high ping.
I've ran a wireshark capture already, that I supplied the support centre team with. I was spectating a game on an EU server when I recorded this capture. The traffic seems to be managed correctly, so I'm wondering if maybe it's a problem with my line?
I use wireless internet, and unfortunately, wired internet is not an option in my current living situation. I get a very strong signal strength, and don't have problems with any other application, so I doubt it's the wireless card that's the culprit.
Thank you to anyone who reads this.

[#2]

Hi PaulMayes,
Is there a way on Dota 2 to see how much bandwidth the game is using?

[#3]

Have you considered some powerline adpaters?
http://www.amazon.co.uk/TP-Link-PA411KIT-AV500-Powerline-Adapter/dp/B0084Y9N3O/ref=sr_1_6?ie=UTF8&qi...

[#4]

Powerline adapters +1
I used to game on wifi and every 5 minutes or so, it would spike and I couldn't do anything. Only solution for me was a long ethernet cable. Never had problem since.

[#5]

I don't think dota2 is properly prioritised for QoS. It's taking lower priority than it should; streaming services are talking first dibs. It's not on the list of specially handled games. I've asked for it to be added and supplied the necessary info (ports and server IPs) but haven't had a useful response.
My bad... seems that I was wrong on this. Just ran Wireshark and the data is 0xA0, as it should be.
But, if I have a 6.5mbit connection, and Netflix uses 3Mbit/s when streaming, DotA only uses (at most) 0.3Mbit/s. The two should be able to co-exist, right?
Instead I get complaints from my son that he's lagging out if anyone tries watching TV.
Something doesn't add up. Any clues?

[#6]

Aha!
http://www.digitalsociety.org/2010/06/how-video-streaming-can-ruin-voip-and-gaming/
Doesn't solve the problem, but does explain why a fast enough connection is still being saturated by Netflix.

[#7]

But Plusnets traffic management should avoid that as long as they have a correct speed set at their end that matches (sort of) your sync speed.

[#8]

Yeah, that shouldn't happen, unless it is your upstream that is being congested.
Have you 100% confirmed that the Dota lagging starts when you start the film? 

[#9]

Yeah, it's very noticeable that any streaming activity on another computer causes DotA to become unplayable. I've monitored this quite a bit, and watched the ping from within DotA jump from ~80-100ms (playable) up to 1000-5000ms as soon as a streaming service begins. I've dropped Netflix quality right down to its lowest, and this does alleviate the problem somewhat in that the lag-spikes don't last so long, but the game still gets unplayable for periods. If nobody is watching TV, the game runs perfectly. Have tried this numerous times, and is definitely the combination of Netflix and gaming that causes the problem.
I raised a ticket on this issue and got a very empathetic and supportive response but, unfortunately, whatever actions were taken appear to have crippled the line further and I'm now only getting 2mbit download, when I used to get 6-7mbit.   The BT Wholesale checker reports my IP profile at 2.5mbit, when it used to be approaching 8mbit.
I'm stumped.

[#10]

Ok, I'll try and get this replicated here.

[#11]

Thanks, Kelly. I appreciate the assistance. Happy to supply logs, screen captures, or whatever else might help.

[#12]

I guess it could be the upload. I've set DSLStats running. Any way to increase the upload bandwidth, or is this line limited?

[#13]

Nope; it's not the upload. Been watching this, and never hitting anywhere near 448kbps as far as I can see - peak was 400kbps for a very short while, but normally much lower.
Good news is that the line has finally retrained at what appears to be a sustainable 7808kbps (SNR varies between 6-7Db). Still getting FEC errors (about 1.1k per hour) but CRC seems to be down to 7 or so per hour, which seems at least passable, no?
But, despite doing everything to monitor and improve the line quality, DotA still lags terribly when I launch a Netlfix stream.

[#14]

Hi,
I've just had a look at this here using a PC with DOTA2 on and an Android running Netflix.
My ping was about 80ms or so normally. It jumped to between 90 and 100 for about 2 seconds when started a Netflix stream, but then went back down to 80 very quickly. I didn't notice any change in the game when this happened.
I played for about 10 minutes while the Netflix was streaming and didn't have any problems and the ping remained static at about 80ms or so.
What device are you running Netflix on? Perhaps we could try and use the same Netflix client that you're using.
Apologies to Kelly for ruining his reputation...!  
Matt
Edit: Just tried with a Windows 7 PC running Netflix - no issues, and also tried Windows + Android concurrently, no problems. Are you using a TV or set top box?
Edit2: Could you try connecting to one of the new BNG gateways? It does traffic management slightly differently and I'd be interested to see if you still get the problem. Load up http://usertools.plus.net/@gateway and look for a gateway with BNG in the name - PCL-BNG01 for instance - and then try again, thanks!

[#15]

Hi
Thanks for the reply. Apologies I didn't see it sooner - truth is, after several contacts with support and trying everything I can think of, I've just been putting up with the problem. It hasn't been any better.
Netflix is perhaps a red herring. Pretty much any data causes the problem. We get pretty good throughput for streaming services, but they ALL seem to take priority over the DotA traffic. Even low-res YouTube videos cause it to crap out.
The devices my family have been using Netflix/4oD/iPlayer/Spotify (not all at the same time, I might add!), etc on range from set top boxes to Android to Windows. I've been monitoring the connection, and it's been variable - periods of stability, with retrains and errors, but settling down eventually somewhere around 6Mbit.
I wondered if WiFi contention was a problem, but this is a 54Mbit Wifi router, right? Still, to remove doubt, I plugged in directly to the router via the cable, and still got problems.
Checked the gateway. All it says is that I'm connected to ptw-ag04. I can't see any option to change anything though. Am I missing something.
Thanks for your help. Would love to solve this and have a harmonious house!