Unstable internet

Start here;

https://forums.xfinity.com/t5/Your-Home-Network/Connection-Troubleshooting-Tips/m-p/1253575#M94474

Post the requested info from here;

https://forums.xfinity.com/t5/Your-Home-Network/Information-Requested-for-Connection-Related-Posts/m-p/1253381#M192739

I have the same problem if directly connected to the modem or using the router.  The same conditions occur almost exactly.

Router is nighthawk AC1900 - R7000

Again it does the same thing with the router attached or no router attached just the modem.

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

Oh and when this happens firefox is still working , bookmarks still work , file open still works , dim function still works , relad page just gets the buffering symbol , just no movement with the internet when this happens , also i don't  know f it pretains , but my cable box the remote selections from menu , to on demand viewing get a lag of about 45 to 60 seconds between any movement to next selection.

Modem is Netgear CM600 , I bought this just for this  account same for the router.

Have you tried any of those tips I supplied ??

I just replied it is an Modem is Netgear CM600

I have turned off modem and router for about an hour then turned on only the modem no router , the same contions start all over.  The same even with the router connected.

I have had this service for about 6 months now.  The bottom light of the modem is always blinking very fast when directly connected to pc.  It seems to slow down when the router in included.  Dslreports speed test is 9.29 megabit/s Down and 5.69 megabit/s up,  Xfinity gives the following -

9.29 megabit/s Down and 5.69 megabit/s up

Xfinity is showing 80.1 Mbps Down and 5.8mbps up , 26ms , IPv4 , Detroit MI

When I am watching a youtube video the video stops playing and the buffering symbol in middle of video keeps going for about 1 minute then starts playing again.

I also get the freeze on other web pages.  Firefox freezes and will not connect to internet , check event viewer there will be some kind of dns server error.

What is the exact make and model number of your cable modem ? 

The SNR is a bit on the low side and it may be intermittently fluctuating even lower to out of spec levels. Perhaps there is some noise ingress into the line(s) somewhere. That can cause random disconnects, spontaneous re-booting of the modem, speed, packet loss, and latency problems.

In a self troubleshooting effort to try to obtain better connectivity, check to see if there are there any excess/unneeded coax cable splitters in the line leading to the modem that can be eliminated/re-configured. Any splitters that remain should be high quality and cable rated for 5-1002 MHz, bi-directional, and no gold colored garbage types like GE, RadioShack, RCA, Philips, Leviton, Magnavox, and Rocketfish from big box stores like Home Depot, Lowes, Target, Wal-Mart etc. Splitters should be swapped with known to be good / new ones to test

If there aren't any unneeded splitters that can be eliminated and if your coax wiring setup can't be reconfigured so that there is a single two way splitter connected directly off of the drop from the street/pole with one port feeding the modem and the other port feeding the rest of the house/equipment with additional splits as needed, and you've checked all the wiring and fittings for integrity and tightness and refresh them by taking them apart then check for and clean off any corrosion / oxidation on the center wire and put them back together again, then perhaps it's best to book a tech visit to investigate and correct.

I'll repeat;

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

here is a cut and paste

Channel Lock Status Modulation Channel ID Frequency Power SNR Correctables Uncorrectables
1                Locked       QAM256   17 573000000 Hz             5.7 dBmV     35.4 dB    21     0
2 Locked QAM256 1 471000000 Hz 7.5 dBmV 37.7 dB 0 0
3 Locked QAM256 2 477000000 Hz 6.8 dBmV 37.4 dB 0 0
4 Locked QAM256 3 483000000 Hz 6.5 dBmV 37.3 dB 0 0
5 Locked QAM256 4 489000000 Hz 6.2 dBmV 37.2 dB 0 0
6 Locked QAM256 5 495000000 Hz 6.6 dBmV 37.2 dB 0 0
7 Locked QAM256 6 507000000 Hz 5.7 dBmV 35.2 dB 0 0
8 Locked QAM256 7 513000000 Hz 5.1 dBmV 36.7 dB 2 0
9 Locked QAM256 8 519000000 Hz 5.5 dBmV 36.8 dB 0 0
10 Locked QAM256 9 525000000 Hz 6.0 dBmV 36.9 dB 2 0
11 Locked QAM256 10 531000000 Hz 6.2 dBmV 37.0 dB 3 0
12 Locked QAM256 11 537000000 Hz 6.0 dBmV 36.9 dB 3 0
13 Locked QAM256 12 543000000 Hz 5.9 dBmV 36.9 dB 1 0
14 Locked QAM256 13 549000000 Hz 6.0 dBmV 36.9 dB 2 0
15 Locked QAM256 14 555000000 Hz 6.0 dBmV 36.8 dB 3 0
16 Locked QAM256 15 561000000 Hz 6.1 dBmV 36.8 dB 8 0
17 Locked QAM256 16 567000000 Hz 5.8 dBmV 35.6 dB 0 0
18 Locked QAM256 18 579000000 Hz 5.8 dBmV 36.5 dB 0 0
19 Locked QAM256 19 585000000 Hz 5.7 dBmV 36.5 dB 0 0
20 Locked QAM256 20 591000000 Hz 5.8 dBmV 36.3 dB 0 0
21 Locked QAM256 21 597000000 Hz 5.6 dBmV 36.3 dB 0 0
22 Locked QAM256 22 603000000 Hz 5.3 dBmV 36.0 dB 0 0
23 Locked QAM256 23 609000000 Hz 5.4 dBmV 35.8 dB 0 0
24 Locked QAM256 24 615000000 Hz 5.8 dBmV 36.1 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 16600000 Hz 40.3 dBmV
2 Locked ATDMA 1 5120 Ksym/sec 35800000 Hz 38.8 dBmV
3 Locked ATDMA 2 5120 Ksym/sec 29400000 Hz 40.3 dBmV
4 Locked ATDMA 3 5120 Ksym/sec 23000000 Hz 40.3 dBmV
5 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
6 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
7 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV
8 Not Locked Unknown 0 0 Ksym/sec 0 Hz 0.0 dBmV

I spaced out the first line.

There is one line from the wall to splitter then from splitter to cable tv box and modem which are near each other .  All connections are tight and no kniks in lines.

I just did another dslreports speed test and it shows 68.3 down and 6.12 up. It also shows comcast all green in the middle circle which is good.

Xfinity speed test is 83.6 down and 5.8 up

I expect there to be some difference between the the two , but earlier it was a huge gap not so much now.

Speakeasy speed test 71.3 down and 6 up to chicago. Earlier it was 12.6 down and new york was only 9. So these three are pretty much agreeing right now. Dslreports , xfinity , and speakeasy.