Hi,
Till a few weeks ago I used to get ~800Mbps download speed on my 1Gbps plan. I was getting this speed for about a year, then suddenly some weeks ago it dropped down to 100Mbps (directly connected the desktop to the modem). I had a CM1200 modem and a Tp-link Deco mesh router. I contacted Xfinity support and a technician came to our house, and checked all signals, coex cable, and ethernet cable, etc. His conclusion -- the signal is good and I should be getting 1 Gbps and the problem is with my modem (CM1200). To reiterate, this modem was working fine for about a year. I took the technician's advice and tested a new modem (CM3000), but I still see the same 100 Mbps. I have tried multiple ethernet cables to rule out any faulty ones.
The log from the modem is
| Startup Procedure |
| Procedure |
Status |
Comment |
| Acquire Downstream Channel |
405000000 Hz |
Locked |
| Connectivity State |
OK |
Operational |
| Boot State |
OK |
Operational |
| Security |
Enabled |
BPI+ |
| IP Provisioning Mode |
Honor MDD |
IPv6 only |
|
|
|
| Downstream Bonded Channels |
| Channel |
Lock Status |
Modulation |
Channel ID |
Frequency |
Power |
SNR |
Correctables |
Uncorrectables |
| 1 |
Locked |
QAM256 |
4 |
405000000 Hz |
2.7 dBmV |
41.3 dB |
0 |
0 |
| 2 |
Locked |
QAM256 |
5 |
411000000 Hz |
2.5 dBmV |
41.2 dB |
3 |
0 |
| 3 |
Locked |
QAM256 |
6 |
417000000 Hz |
2.3 dBmV |
41.1 dB |
3 |
0 |
| 4 |
Locked |
QAM256 |
7 |
423000000 Hz |
2.3 dBmV |
41.2 dB |
4 |
0 |
| 5 |
Locked |
QAM256 |
8 |
429000000 Hz |
2.1 dBmV |
41.0 dB |
4 |
0 |
| 6 |
Locked |
QAM256 |
9 |
435000000 Hz |
2.2 dBmV |
41.0 dB |
1 |
0 |
| 7 |
Locked |
QAM256 |
10 |
441000000 Hz |
2.0 dBmV |
41.0 dB |
4 |
0 |
| 8 |
Locked |
QAM256 |
11 |
447000000 Hz |
1.9 dBmV |
40.9 dB |
7 |
0 |
| 9 |
Locked |
QAM256 |
12 |
453000000 Hz |
1.7 dBmV |
40.8 dB |
6 |
0 |
| 10 |
Locked |
QAM256 |
13 |
459000000 Hz |
1.6 dBmV |
40.6 dB |
9 |
0 |
| 11 |
Locked |
QAM256 |
14 |
465000000 Hz |
1.5 dBmV |
40.7 dB |
457 |
1786 |
| 12 |
Locked |
QAM256 |
15 |
471000000 Hz |
1.1 dBmV |
40.4 dB |
2 |
0 |
| 13 |
Locked |
QAM256 |
16 |
477000000 Hz |
1.0 dBmV |
40.4 dB |
12 |
0 |
| 14 |
Locked |
QAM256 |
17 |
483000000 Hz |
0.8 dBmV |
40.4 dB |
9 |
0 |
| 15 |
Locked |
QAM256 |
18 |
489000000 Hz |
0.8 dBmV |
40.3 dB |
7 |
0 |
| 16 |
Locked |
QAM256 |
19 |
495000000 Hz |
0.6 dBmV |
40.2 dB |
7 |
0 |
| 17 |
Locked |
QAM256 |
20 |
507000000 Hz |
0.5 dBmV |
39.9 dB |
11 |
0 |
| 18 |
Locked |
QAM256 |
21 |
513000000 Hz |
0.3 dBmV |
40.1 dB |
17 |
0 |
| 19 |
Locked |
QAM256 |
22 |
519000000 Hz |
0.3 dBmV |
40.1 dB |
11 |
0 |
| 20 |
Locked |
QAM256 |
23 |
525000000 Hz |
0.1 dBmV |
40.0 dB |
15 |
0 |
| 21 |
Locked |
QAM256 |
24 |
531000000 Hz |
0.1 dBmV |
40.1 dB |
10 |
0 |
| 22 |
Locked |
QAM256 |
25 |
537000000 Hz |
-0.1 dBmV |
39.9 dB |
19 |
0 |
| 23 |
Locked |
QAM256 |
26 |
543000000 Hz |
0.0 dBmV |
40.0 dB |
15 |
0 |
| 24 |
Locked |
QAM256 |
27 |
549000000 Hz |
0.0 dBmV |
39.9 dB |
16 |
0 |
| 25 |
Locked |
QAM256 |
28 |
555000000 Hz |
-0.2 dBmV |
39.8 dB |
17 |
0 |
| 26 |
Locked |
QAM256 |
29 |
561000000 Hz |
0.2 dBmV |
40.0 dB |
19 |
0 |
| 27 |
Locked |
QAM256 |
30 |
567000000 Hz |
0.3 dBmV |
40.0 dB |
17 |
0 |
| 28 |
Locked |
QAM256 |
31 |
573000000 Hz |
0.3 dBmV |
40.1 dB |
11 |
0 |
| 29 |
Locked |
QAM256 |
32 |
579000000 Hz |
0.5 dBmV |
40.1 dB |
12 |
0 |
| 30 |
Locked |
QAM256 |
33 |
585000000 Hz |
0.5 dBmV |
40.2 dB |
13 |
0 |
| 31 |
Locked |
QAM256 |
34 |
591000000 Hz |
0.5 dBmV |
40.2 dB |
4 |
0 |
| 32 |
Not Locked |
Unknown |
0 |
0 Hz |
0.0 dBmV |
0.0 dB |
0 |
0 |
|
|
|
| Upstream Bonded Channels |
| Channel |
Lock Status |
US Channel Type |
Channel ID |
Symbol Rate |
Frequency |
Power |
| 1 |
Locked |
ATDMA |
4 |
5120 Ksym/sec |
29200000 Hz |
38.8 dBmV |
| 2 |
Locked |
ATDMA |
2 |
5120 Ksym/sec |
16400000 Hz |
38.8 dBmV |
| 3 |
Locked |
ATDMA |
3 |
5120 Ksym/sec |
22800000 Hz |
38.5 dBmV |
| 4 |
Locked |
ATDMA |
5 |
5120 Ksym/sec |
35600000 Hz |
38.8 dBmV |
| 5 |
Locked |
ATDMA |
11 |
2560 Ksym/sec |
40400000 Hz |
39.3 dBmV |
| 6 |
Locked |
ATDMA |
1 |
2560 Ksym/sec |
10400000 Hz |
39.5 dBmV |
| 7 |
Not Locked |
Unknown |
0 |
0 |
0 |
0.0 dBmV |
| 8 |
Not Locked |
Unknown |
0 |
0 |
0 |
0.0 dBmV |
|
|
|
| Downstream OFDM Channels |
| Channel |
Lock Status |
Profile ID |
Channel ID |
Frequency |
Power |
SNR / MER |
Active Subcarrier
Number Range |
Unerrored
Codewords |
Correctable
Codewords |
Uncorrectable
Codewords |
| 1 |
Locked |
0 ,1 ,2 ,3 |
48 |
850000000 Hz |
-4.52 dBmV |
36.9 dB |
1108 ~ 2987 |
288191827 |
228855759 |
0 |
| 2 |
Not Locked |
0 |
0 |
0 Hz |
0 dBmV |
0 dB |
0 ~ 4095 |
0 |
0 |
0 |
|
|
|
| Upstream OFDMA Channels |
| Channel |
Lock Status |
Modulation / Profile ID |
Channel ID |
Frequency |
Power |
| 1 |
Not Locked |
0 |
0 |
0 Hz |
0 dBmV |
| 2 |
Not Locked |
0 |
0 |
0 Hz |
0 dBmV |
|
Would appreciate any help.
Accepted Solution
user_e1b317
3 Messages
10 months ago
After debugging a bit, the issue turned out to be the qos setting in the tp-link Deco router that I have been using. A few months ago qos on the router was enabled, but I noticed now that for some reason there is a cap of 100 Mbps in the settings, I think this setting was somehow forcing the ethernet port of the router to negotiate the rate at 100 Mbps between router and modem. By disabling the qos now I can see that I am getting close to 800 Mbps data rate. At the end I did not need a new modem. My old modem cm1200 was sufficient. Appreciate the support Xfinity provided.
0
0
XfinityArmand
Official Employee
•
2.1K Messages
10 months ago
Hi there @user_e1b317! Thank you so much for taking the time to reach out to Xfinity Support here on our Community Forum. We are so glad to hear from you and happy to help in any way that we can to address your service concerns. No worries! You have reached out to the right team, and we are going to help get things squared away. So that we can get started, please feel free to shoot us a private message with your details and we'll get the ball rolling.
To send a "direct message" / "private message" message to Xfinity Support:
• Click "Sign In" if necessary
• Click the "Direct Message" icon or https://forums.xfinity.com/direct-messaging
• Click the "New message" (pencil and paper) icon
• The "To:" line prompts you to "Type the name of a person". Instead, type "Xfinity Support" there
• - As you are typing a drop-down list appears. Select "Xfinity Support" from that list
• - An "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
0
0
EG
Expert
•
110.1K Messages
10 months ago
@user_e1b317 @XfinityArmand
Please circle back here and post any possible solutions for the issue here in these open public forums so that all readers here may benefit from the exchange / info. This is in keeping with the spirit for which these public help forums were originally intended. Thank you.
2
0
EG
Expert
•
110.1K Messages
10 months ago
Thanks for the update ! Glad you got it figured out !! Now closing your marked Solved topic.
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