Severe Speed Degradation - T3 Timeout Errors - Need Technician Dispatch

Dear Xfinity/Comcast Support Team,

I am experiencing severe internet speed degradation. After extensive troubleshooting on my end, the following issues remain unresolved and are beyond the scope of router-level software fixes. I am requesting your direct intervention.

Modem: Motorola MB8600 (DOCSIS 3.1)

Background - Diagnostics Already Performed:
- Verified all Ethernet connections are gigabit-capable (CAT6 cables, gigabit NIC, gigabit router ports)
- Confirmed router LAN/WAN negotiation at 1.0 Gbps full duplex
- Disabled QoS/bandwidth control and parental controls on the router
- Changed DNS servers to Google DNS (8.8.8.8 / 8.8.4.4)
- Rebooted and renewed WAN lease multiple times
- Ran speed tests on Speedtest.net and Fast.com with consistently poor results (6-46 Mbps)
- Found numerous T3 timeout errors in the modem SNMP event log, indicating signal-level issues between my modem and the CMTS

Action Items Requiring ISP Support:

1. Check Coaxial Cable Connections - Ensure the coaxial cable from the wall outlet to the modem is securely tightened, undamaged, and not excessively bent.

2. Remove Extra Signal Splitters - If there are any splitters on the coaxial line, please test with a direct connection to rule out signal loss.

3. Line and CMTS Inspection (T3 Timeout Errors) - T3 timeout errors typically require an ISP technician to inspect the line and CMTS-side configuration. Please:
- Check and refresh my modem provisioning file
- Confirm whether my subscribed plan speed is gigabit
- Check if the CMTS node in my area has congestion or faults

4. Confirm My Xfinity Plan - Current measured speeds (15-46 Mbps) may reflect the actual subscribed plan speed rather than a gigabit plan. Please verify my account and confirm the subscribed tier.

5. Dispatch a Technician - If remote troubleshooting cannot resolve the T3 timeout errors and speed issues, please schedule an on-site technician visit to inspect the coaxial line, connectors, and signal levels at my address.

I can provide my account details and address via private message. Thank you for your prompt attention.