MTU for XBOX live mutliplayer gaming on 5g home broadband

[Lexx289]

I am struggling to get my Xbox to work on Xbox live. Doing some googling it seems that the MTU is too low, it is 1360 and should be about 1385 to be able to work properly. I have rung three who seem to have no knowledge of what an MTU is and have sent me to the ombudsman. I have logged into the router (H122-373) and increased the MTU manually however it will not pull through onto my XBOX. I have put it in the DMZ, enabled UPNP and generally faffed with it as much as i can but the MTU on the XBOX does not change. I am assuming this is what is being sent from three and so it is something to be changed at three's end...

Does anyone else have any experience of this, or have any issues with XBOX live and home broadband 5g? or can they get it to work, cheers

[JimmyRobin]

I have not resolved this problem yet, however this is what my research has taught me so far.

MTU is basically packet sizes of data. If a data packet is too large it gets fragmented into smaller packets which can clog the system. The 'standard' router MTU setting is 1500. You'll need to reduced the maximum size of the 'data packet' to stop fragentation which should increase your internet speed.

Please follow this tutorial on how to do it. 

https://youtu.be/RK2PHpKI9M4?si=GY9TYs-tCPVwJneQ

My ZTE router's MTU is now set to 1380 and MSS set to 1340 so fragmentation no longer occurs however Xbox still shows an MTU error (MTU is too low) This can only be addressed by THREE NETWORK. In my opinion, until this happens, Three's 5G broadband is simply unusable for online xbox gaming. 

Basically the MTU on Three's network is too small so fragmentation happens at lower sized data packets than on other networks because their MTU value is higher. Xbox recognises this and throws up the error and online gaming suffers as a result.

[JimmyRobin]

To add further and update, I also made sure the NAT was open in the Xbox settings by choosing a different port number (advanced Network Settings)

It’s only been a couple of days now but so far everything seems to be working ok. 🤞

[JohnM]

Hey @JimmyRobin 

Wanted to check in, is this solution you have found still working?

The default MTU for the network is 1500 but we have found this shows a lower value when there is issues with coverage or congestion on the Network.

Does the network status checker show there is work being done in the area?

John M 

[Ccbustion90]

I'm having issues with the party chat on Xbox as others have mentioned. Has a solution been found to this issue?

[KINGY2468]

Having previously been able to play with no issues I now cannot get any of the party chat features to connect and despite UPnP settings being open my NAT type is showing as moderate. This is ridiculous that a problem has been going on this long with no resolution 😞

[DontMindMe4524]

Just got my Three broadband yesterday. Read the whole thread. Describes my exact issues.

Luckily I get good speeds and actually managed to play some online games (Smite) without a problem, even though I get the MTU problem. However last night during peak times I was getting 100% packet loss and not able to play anything.

I'll test the speeds/packet loss again tonight. If it's just during peak hours I might be able to work around it. But I'll also have to see how this is gonna work with my streaming...

[CSpec01]

I read @TheJunglist's post and reapplied UPnP enabled (as it was already enabled from my previous attempts of solving this) and it appeared to solve the MTU problem! Until I tested the connection again 5 seconds later... 

Disabling the router firewall also appears to temporarily fix the problem too, but of course not ideal.

If I were to guess, as someone who knows only the basics about networking, neither of these are actually solving the issue but that something happens during the period the router updates its settings where the MTU issue is fixed for a small moment? 

[MrSimo98]

Sadly I ended up returning my Three 5G router. Although the speeds were great for me this MTU problem was really effecting my online experience.

I was told I would have a phone call from three to discuss this issue and I hadn’t heard a thing. Sorry guys but don’t think this will be sorted out. 

[Chris7197]

Is there any news on this? It’s also causing me real problems on Xbox where certain games do not work online most of the time, and the Xbox multiplayer test points to the MTU being a problem 

[Cerberus73]

1360MTU won’t cut it for Xbox’s online service anymore. Being that it’s at THREE’s end why haven’t they done anything about it ? it’s over halfway through 2023 and still not resolved ?

Customer service eh 😂🤣🤣 ffs!