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Stability Issue with Home Internet5G – Contract

  • November 26, 2025
  • 6 Antworten
  • 54 Aufrufe
M
Besucher:in


I live in Munich, and I am fortunate to have excellent reception conditions of O2 5G network. I decided to use O2’s unlimited home internet service based on a SIM card."

And now I have a serious and persistent problem with my home  sationary  5G acses point ( TP-Link DECO X50  5g  (HW 2) ) internet service whit O2 SIM card. From the very beginning, I experienced minor difficulties when using multiple devices at home. However, the situation has significantly worsened: I currently have around 10 devices connected, and the internet has become almost unusable.

Whenever any medium-demand activity occurs on any device, the entire household experiences a complete slowdown. For example:

  • Opening any website with multiple connections or heavy advertisements often causes the internet to fail for all users.

  • When my spouse and I work on corporate laptops simultaneously, the internet stops working after about 10 minutes and remains unavailable for 1–2 hours .

Observed Symptoms:

  • Loss of pings to all resources except O2 DNS server.

  • Pages with many ads or with many connections  can take 5–10 seconds to load, causing severe speed drops for all devices  in home network.

  • After approximately 30 minutes of active usage or surfing, the internet slows down further and eventually stops entirely.

  • Opening the Speedtest website (even without running a test) breaks the internet connection in the house.

 

  •  

Troubleshooting Already Performed:

  1. Multiple correspondences with the router manufacturer (TP-Link Deco X50 5G).

  2. Three remote sessions with technical support  TP-Link. No issues were found with the router.

  3. Testing with O2 SIM cards in a phone and USB Ethernet tethering - shows similar behavior: opening Speedtest, heavy-ad websites, and sites from other domains immediately causes packet loss and ping interruptions.

Based on my observations, this cannot be considered normal. Other causes, such as poor wiring or Wi-Fi interference, can be excluded:

  • Packet loss occurs even on wired connections.

  • Pings directly from the router also show the same loss.

  • Pings to O2 primary  DNS servers remain stable at all times.

This strongly suggests that the packet loss and speed degradation are caused by O2’s handling of my traffic, rather than any network or device issues on my side.

I kindly request that you investigate this matter urgently and provide a solution. I believe the issue may relate to traffic analysis, ad targeting, or other similar O2 functions. Please immediately disable any such functions affecting my connection and confirm this action in massege.

Thank you for your prompt attention to this critical issue. I look forward to your response.

Regards, Mikhail.

 

edit o2_Manga: Rufnummer aus Titel entfernt.

6 Antworten

o2_Manga
  • o2_MangaModeratorin
  • November 28, 2025

Hi ​@Mikhail99 

welcome to our community. Pleasure to meet you. 🙂

Did you use our Livecheck to look for an issue in your area? If there is nothing shown you can report a problem by using the button “Störung melden”

Please try the SIM card in another device to get more information about the problem. Does the error occure in a smartphone as well, it could be a defective SIM. 

If everything is working properly the router might have a disturbance. 

Greetings

Manga

 

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M
Besucher:in
  • Mikhail99
  • Autor
  • Besucher:in
  • November 28, 2025

Hello Manga,

Thanks for your reply.

I want to clarify that all the basic checks you mentioned have already been done — thoroughly and several times. Below is a short summary of the facts that clearly rule out a faulty SIM card, router issue, or any local Wi-Fi/LAN problem:

  1. The issue appears on different devices and different “routers”.
    Using the O2 SIM in a smartphone with USB-tethering produces the same packet loss.
    A different SIM (Lycamobile / Vodafone) in the very same router shows no interruptions.

  2. It’s not Wi-Fi and not LAN related.
    Packet loss happens on wired Ethernet.
    Packet loss happens when pinging directly from the router.
    The local network is completely stable.

  3. O2 DNS servers stay 100% reachable — even during outages.
    Pings to the O2 DNS never drop. (62.109.121.17).
    At the same time, all other external IPs show 50–100% loss.
    This alone already excludes a broken SIM, faulty router, or local interference.

  4. Three remote sessions with TP-Link support confirmed the router works correctly.
    They watched the logs live.
    During the outage, they saw 100% loss to any destination except O2 DNS
    Their conclusion was clear: the router is not the source of the problem.

  5. The problem only appears under specific O2 traffic conditions.
    Opening Speedtest or other high-load websites immediately breaks connectivity.
    This behaviour is fully reproducible and definitely not normal for 5G.

For these reasons, this is not a SIM card issue, not a router hardware issue, and not a Wi-Fi/LAN setup problem.
It is very clearly a network-side problem, and I kindly request that this case be forwarded to the technical department (Technik / Netztechnik) rather than general support.

Also, I honestly doubt that a website like forbes.com — overloaded with ads — is somehow “breaking my internet” because of a router problem or  foulty sim card.  This kind of explanation doesn’t hold up technically. It looks much more like some form of restriction or behaviour on the network side.

And just to be absolutely clear: I would gladly test with an O2-provided, guaranteed-working router if you can supply one. That would allow us to completely exclude any potential TP-Link fault.

Please confirm that my request has been forwarded to the appropriate technical team.

Thank you,
Mikhail

o2_Gerrit
  • o2_GerritModerator
  • Moderator
  • December 5, 2025

Hello ​@Mikhail99,

good that you send a request for checking for a disturbance to our technikcal deportment.

Whereas our live check does as of now not report a disturbance or restrictions for your address, the colleagues did detect an impairment and are working on a solution.

Please keep us also updated here 🙂

Best regards,

Gerrit

A
Besucher:in
  • alp0302
  • Besucher:in
  • January 10, 2026

Hello, 

I live in Bonn, and I have the same problem unfortunately. Is there any progress through the problem? I have already reported the problem through "störung o2" website. However they have checked and said there are no problems according to their tests.

I have contacted with my routers support service and checked forums. Every o2 user has the same issue as we do. This issue started in summer, probably late August as far as I remember.

 

If there is any solution, I would love to hear. Otherwise I will try to find another solution by reporting failing internet to o2 and hope for a fix.

Thank you

A
Besucher:in
  • alp0302
  • Besucher:in
  • January 10, 2026

Hello again,

 

I have found a good solution which will probably fix a lot of peoples problems. The issue was actually a very small detail; Authentication Type. It is default CHAP, however if you switch it to PAP it will be fixed. A person who dealed with the same issue has written in the forum; 

If you follow this guide it will help you, as it fixed my whole problem at once. 

 

Kind regards 

o2_Manga
  • o2_MangaModeratorin
  • January 10, 2026

​@Mikhail99 

thank you for the feedback. Glad to hear you found a solution.

We will share it with other users as soon as anyone faces the same problem. 

If there are other topics you would like to discuss please do not hesitate to get back right here.

Greetings

Manga

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