U

Visitor

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2 Messages

Saturday, September 17th, 2022 12:56 AM

MB8611 can only reach about 1/3 (300 Mbps) of the speed I paid for (900 Mbps)

I already contact Comcast twice in the past 6 months. And Technician also came out twice to confirm my line can reach 1Gbps. However, my MB8611 still only reaches around 300 Mbps with both thru my router or direct PC connection to the modem. My Pwr is between 6 to 8 dBmV. SNR is between 36 to 38 dB. I search on the forum and it seems that someone solved this issue by loading the correct boot file. Could someone help to check my modem if it is loaded with the correct boot file?

XfinityJohnG

Official Employee

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231 Messages

4 months ago

Thank you very much for reaching out to us here @user_6f46da. I would be happy to ceck on that bootfile from here for you. Could you send me a direct message with the full name and complete address for your service? 

 

To send a direct message [private message]:

   Click the "Direct Message" icon or  https://comca.st/3LqDtsl

   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

Visitor

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2 Messages

@XfinityJohnG​ , I just send a direct message. Please check.

Thanks in advance.

Visitor

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2 Messages

4 months ago

Having the same issue with the same modem mb8611. Paying for 900 MBPS and only getting 300 MBPS.   Did you get your issue resolved?

(edited)

Visitor

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2 Messages

4 months ago

Also have MB8611....paying for 1.2 Gbps and only getting between 300-400 Mbps. 

Also interested if you had any luck getting this resolved.

XfinityEthan

Official Employee

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1.2K Messages

@user_9c78bd. We can definitely help with your speed issue and don't hesitate to make your own post when you have issues. The main factor is slow speeds is physical impairments and hardware issues. We recommend CAT 6 or above cables and a computer with a 1GB+ port. I checked on your signal and there are some issues that might require a technician. Direct message your name and address and we can work on it.

 

Make sure you are signed into forums

1. In the top right corner, you'll see a little chat icon(direct message) near the bell icon. 2. Click the "New message" (pencil and paper) icon

2. Hit the compose button to the right of "conversations"

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!

 

 

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.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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2 Messages

4 months ago

i also have a MB8611 run with cat 8 that will only pull 300 mbps on the 1200 plan

Visitor

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2 Messages

lots of the below errors repeating one after the other on the event log of the modem 
SYNC Timing Synchronization failure - Failed to acquire QAM/QPSK symbol timing
No Ranging Response received - T3 time-out

Visitor

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2 Messages

I have the same repeating error message and also have 

SYNC Timing Synchronization failure - Loss of Sync;CM-MAC......

Comcast checked my line remotely (while I was in a chat session) yesterday and saw something that might be an issue so I setup a visit from one of their technicians.

I also received a voice message this morning indicating that overnight an issue related to my service was identified and corrected (I assume remotely) and asking if I still want to keep my appointment with the service tech. I checked speed and it is still 300-400 Mbps so I will see if the tech finds anything.

Official Employee

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372 Messages

Hi @user_f17ee0,

We would be more than happy to look into your Internet speed concerns. Could you please send our team a direct message with your full name and full address? Our team can most definitely take a further look at this issue.

To send a "Peer to peer" ("Private") message:

Click "Sign In" if necessary

• Click the "Peer to peer chat" icon

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

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

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.
Was your question answered? Please, mark a reply as the Accepted Answer.tick

Visitor

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2 Messages

Still having the same issue.  Did anyone get it resolved?  360 MBPS, which is fast, but I'm paying for 1 GBPS.  Other users on these forums are saying that the wrong bootfile is being used.  The fact that Xfinity still hasn't figured this out doesn't give me much hope...

Official Employee

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280 Messages

@user_0d57e7, Please let us know if you are still having issues with your internet speed. We would be happy to help. 

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.
Was your question answered? Please, mark a reply as the Accepted Answer.tick
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