400 Mbps plan but getting just under 300 Mbps

They're good. Please also post the upstream power values.

Can't see your pic. Since you are a new poster, it needs to be approved by a Forum Admin. That could take some time. In the interim, you could try hosting it at one of those free third-party pic hosting sites like Imgur or Photobucket and post the link to it here.

Or copy all of the text of the status page and paste it into the body of your next post here.

Looks like the image with modems levels didn't post - here they are

Connection Status
System Up Time 2 days 08h:06m:33s

Network Access Allowed

Downstream Bonded Channels

Channel Lock Status Modulation Channel ID Freq. (MHz) Pwr (dBmV) SNR (dB) Corrected Uncorrected
1 Locked QAM256 24 483.0 -1.3 41.1 0 0
2 Locked QAM256 25 489.0 -1.5 40.9 0 0
3 Locked QAM256 26 495.0 -1.7 40.7 0 0
4 Locked QAM256 27 507.0 -1.3 35.5 0 0
5 Locked QAM256 28 513.0 -1.2 41.1 0 0
6 Locked QAM256 29 519.0 -1.2 41.1 0 0
7 Locked QAM256 30 525.0 -1.1 41.1 0 0
8 Locked QAM256 31 531.0 -1.2 40.9 0 0
9 Locked QAM256 32 537.0 -1.2 40.9 0 0
10 Locked QAM256 33 543.0 -0.9 41.1 0 0
11 Locked QAM256 34 549.0 -0.9 41.2 0 0
12 Locked QAM256 35 555.0 -0.7 41.3 0 0
13 Locked QAM256 36 561.0 -0.9 41.3 0 0
14 Locked QAM256 37 567.0 -0.9 41.2 0 0
15 Locked QAM256 38 573.0 -0.7 41.3 0 0
16 Locked QAM256 39 579.0 -0.4 41.7 0 0
17 Locked QAM256 40 585.0 -0.4 43.3 0 0
18 Locked QAM256 41 591.0 -0.3 43.1 0 0
19 Locked QAM256 42 597.0 -0.2 43.0 0 0
20 Locked QAM256 43 603.0 0.0 43.0 0 0
21 Locked QAM256 44 609.0 0.7 43.1 0 0
22 Locked QAM256 45 615.0 1.2 43.5 0 0
23 Locked QAM256 46 621.0 1.6 43.8 0 0
24 Locked QAM256 47 627.0 1.6 43.4 0 0
Total

For whatever reason this area has always had 5 upstream channels - signal levels below.

Connection to modem is a single cable from the street into the house installed by Xfinity a few years ago. No connectors, splitters - just one cable into the modem.

Upstream Bonded Channels

Channel Lock Status Channel Type Channel ID Symb. Rate (Ksym/sec) Freq. (MHz) Pwr (dBmV)
1 Locked ATDMA 1 5120 17.3 47.0
2 Locked ATDMA 2 5120 23.7 47.3
3 Locked ATDMA 3 5120 30.3 48.3
4 Locked ATDMA 4 5120 36.7 47.0
5 Locked ATDMA 5 1280 41.2 45.0
6 Not Locked Unknown 0 0 0 0.0
7 Not Locked Unknown 0 0 0 0.0
8 Not Locked Unknown 0 0 0 0.0

They are in spec as well. Try calling 1-800-comcast and ask a rep to completely remove the modem from your account and to "re-provision" it from scratch. Also ask them to confirm that the provisioning and account data in their database is correct and complete and that the correct configuration / bootfile for your subscribed to speed tier is being pushed to the modem. Good luck !

I'm going to escalate your issue to the Comcast corporate employees that are available to these boards. You should get a reply here in your topic. Good luck !

In my experience calling the Comcast 1-800 and asking those type of questions is hard.

The first level support have their scripts which they stick  to (restart the modem etc). Getting someone who can actually tell you speed the modem is provisioned with is much harder.

I was kind of hoping the forums might suggest a better way to actually reach someone who can help.

I know the signal levels are within spec - but was posting here as thought would be the first questions people ask and wanted to get beyond that.

Oh well..

Hi, vandergraff. Thank you for bringing this speed concern to our attention! We can definitely take a look at your account to see what is going on with your current level of speed, along with the upgrade that was supposed to take place. We will figure everything out from there. To begin, please send me a PM with your first and last name.

To send a private message, please click my name "ComcastMorgan" then select "Send a Message" on the right side.  

Thanks! Talk soon.

Any luck in contacting a Comcast employee on these boards to assist with this?

Thanks

We're glad you were able to fix the issue! This is great news 🙂 Thanks again for all your time and help. Good catch reviewing your router settings. Do all you can to have a great night and please send us another message anytime if needed. Take care

Hello if anyone is out there,

My plan just upgraded from 200 to 400/20 mbps yesterday, I have rebooted my routers (ASUS RT-AC68U) but still getting the same speed as before (around 230/12 mbps). 

I also restarted my modem ARRIS 6190 (DOCSIS 3.0).

Any one can re-provision my modem or tell me how to get the speed I'm paying for?

Thanks,