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Visitor

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2 Messages

Wednesday, June 4th, 2025 11:12 AM

Upload speed capped at 40mbps after next-gen upgrade

Just like this thread: https://forums.xfinity.com/conversations/customer-service/just-upgraded-to-an-arris-s34-but-still-only-getting-40-mbps-upload-speed/67c6550183fffd6eaec912c7

There was no resolution listed in that thread but my issue is almost the exactly the same.

Upgraded just this past weekend to 2100/300 after receiving notice that this was available in my area.

Bought a Arris S34 to upgrade my previous S33. Activated it through the Xfinity App and it worked great. Download speeds are > 2000 Mbps but upload speed on multiple tests are hard capped at 40.

The S34 is going to a Ubiquiti Dream Router 7 using the 2.5Gbps WAN port. Using a 10Gbps ethernet cable from the DR7 2.5Gbps lan port to my PC which has a 2.5 Gbps nic. I've also tried directly from the Modem to my PC which is the same, great download (>2Gbps) but capped at 40 Mbps for upload.

I've power cycled everything down chain from the modem to the DR7 to my PC multiple times. I've replaced and tested different cables (brand new Ubiquiti 10G cables).

Just wondering if any techs/support have seen a quick fix for this issue.

Accepted Solution

Official Employee

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2.6K Messages

2 days ago

Hello, @user_x5lk5s

Could you please send our team a direct message with your full name and full address? To send a direct message:

1. In the top right corner, you'll see a little chat icon near the bell icon. Click the direct message icon

2. Click the "New message" (pencil and paper) icon

3. In the 'To' line, type "Xfinity Support" there. A drop-down list appears. Select "Xfinity Support" from that list (an "Xfinity Support" graphic replaces the "To:" line)

4. Type your message in the text area near the bottom of the window

5. Press Enter to send it. An official employee, such as myself or whoever is first available, will respond. Thanks!

Visitor

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2 Messages

Just for anyone reading this I opened a PM with support, gave them my modem mac and they fixed it on their end within 20 minutes or so. Getting 360+ upload now. Thanks again!

Official Employee

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2.6K Messages

@user_x5lk5s We want to thank you for reaching out on the Community Forum for support with your Internet Connectivity issue. We are glad we were able to resolve your issue by activating the proper equipment. Never hesitate to create another public post for any of your future account and service needs!

I am an Official Xfinity Employee.
Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
We ask that you post publicly so people with similar questions may benefit from the conversation.
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