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user_port14
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Sunday, December 28th, 2025 6:07 AM

Persistent Packet Loss & Upstream Node Issue — Modem & Splitter Replaced, Still Losing Packets

Hello — I’m experiencing intermittent packet loss and service disruptions that are confirmed via diagnostics to occur upstream of my home network, and I need help escalating this to a network/node maintenance ticket.

I have already:

  • Replaced the modem with a new unit through an onsite tech visit
  • Replaced the splitter and coax cable from the splitter to the modem
  • Installed a 2.5 Gbps PCIe network adapter and Cat6/Cat8 cabling
  • Verified no internal packet loss or hardware issues

Test results show:

  • Clean pings to 10.0.0.1 and LAN devices
  • Pathping diagnostics show ~95–100% packet loss at the first Comcast hop (upstream node / CMTS)
  • Speeds reach ~2400 Mbps on my 2.1 Gbps plan, but packet loss persists
  • Work-from-home video calls and stable connections are still impacted

This issue is not a premise problem, nor is it related to my equipment or wiring at home.

Please escalate this to network maintenance / line maintenance so the upstream path (tap/node/CMTS) can be investigated for noise, ingress, or failure.

Thanks.

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1 month ago

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user_port14

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1 month ago

Diagnostic Summary (Confirmed Upstream Issue)

Service Address: Doral, FL 33178

Connection: Wired (2.5 Gbps PCIe NIC, Cat6/Cat8)

Gateway: Xfinity Gateway (recently replaced by technician)

PACKET LOSS TESTING

Command used: code:”pathping 8.8.8.8”

 

Results observed:

  • Hop 1 (10.0.0.1 / Gateway): 0–1% packet loss
  • Hop 2 (First Comcast node / CMTS): ~95–100% packet loss
  • Packet loss begins upstream of the modem, not inside the home

This confirms the issue is occurring on Comcast’s network side, not customer equipment.

GATEWAY / SPEED DIAGNOSTICS

  • Plan speed: 2100 Mbps
  • Speed to Gateway (Xfinity app):
    • Before replacing splitter/coax: ~1200–1300 Mbps
    • After replacing splitter & coax: ~2400 Mbps (116% of plan)

Throughput improved, but packet loss persists, indicating upstream noise or node instability rather than bandwidth limitation.

CUSTOMER-SIDE TROUBLESHOOTING COMPLETED

  • Modem replaced by Xfinity technician
  • Coaxial connection replaced by technician
  • Splitter replaced
  • New 2.5 Gbps PCIe network card installed
  • Ethernet cables replaced and tested
  • Local network tests clean

All customer-side equipment and wiring have been ruled out.

IMPACT

  • Intermittent packet loss disrupts work-from-home video calls
  • Real-time traffic affected despite high throughput
  • Issue is intermittent, consistent with node ingress or upstream noise

REQUEST

Please escalate this issue to Network / Line Maintenance to investigate:

  • Upstream noise or ingress
  • Failing tap or amplifier
  • Node / CMTS instability
  • Outside plant signal quality

A premise technician visit has already occurred and did not resolve the issue.

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XfinityChristy

Official Employee

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2.7K Messages

@user_port14 Hello! Thank you for sharing such a detailed and professional breakdown of your connection diagnostics. We truly appreciate the time and effort you’ve put into isolating these results—it is immensely helpful for our team to see that Hop 2 data and the steps you've already taken to rule out local equipment.

We can certainly understand the frustration of having excellent download speeds but persistent packet loss, especially when it disrupts your work-from-home stability. It’s clear that after the equipment swaps and wiring updates, we need to take a deeper look at the network side to ensure everything is performing as it should in your area.

We would like to get this information over to our specialized technical team to investigate the node and upstream health further. Please send us a Direct Message with your full name and service address, so we can pull up your account and get this moving in the right direction for you. We're ready to help!

 

To send a "Direct Message":

Click "Sign In" if necessary

Click the "Direct Messaging" icon at the top of the page (it looks like a text bubble)

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

Type "Xfinity Support" in the "To:" line and select "Xfinity Support" from the drop-down list that appears. The "Xfinity Support" graphic replaces the "To:" line

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

Press Enter to send it

 

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Official Employees are from multiple teams within Xfinity: CARE, Product, Leadership.
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1 month ago

user_port14

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Thank you for the response.

I’ve sent a Direct Message to Xfinity Support with my account details so this can be escalated to the appropriate network maintenance team.

I appreciate the assistance.

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1 month ago

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