Need Help with Intermittent Internet Issues

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darkgiants

New Around Here
For the last five months, I have been having intermittent internet issues where my internet slows down to an absolute crawl, to a point where it is unusable and is insanely slow. This requires either rebooting my modem (Comcast Modem, ARRIS TG3482G which is set in Bridge mode) and/or my router (ASUS RT-AC68U running Asuswrt-Merlin 384.18). At first, I thought it was an issue with my power levels and the overall signal coming through Comcast, but I have noticed that the ranges are in the acceptable range from Comcast (though a bit on the higher side, but these levels have been pretty consistent for years). Though recently, I have realized a faster way to resolve these intermittent internet issues/slow-downs that doesn't require rebooting the modem and/or router, but instead simply logging into the Asuswrt-Merlin configuration page and doing the following steps:
  1. Click on 'Network Map'
  2. Next, click on the Globe icon
  3. Click on 'Internet Connection' toggling it to 'Off'
  4. After a few seconds later, I click on 'Internet Connection' and toggle it back to 'On',
Doing these steps somehow resolves the internet issues now, without having to reboot my cable modem nor the router. Of course, it does take some time for the next episode of the internet slow-down to appear requiring to re-do the steps mentioned above. Another thing I would like to also note is when I do the steps above, or a reboot to resolve the internet slowdowns, accessing the modems configuration page (and not the router) via '10.0.0.1' does not appear to load immediately, but it takes 30 minutes to an hour for it to become available. No idea why this may be the case. I have tried quite a few things and even tried to dig through the logs but there is nothing that really shows why these issues may be happening. Some of the things I have already done are:
  • Switch my DNS servers to Quad9 (9.9.9.9)
  • Set my DHCP query frequency to 'Normal Mode' from 'Aggressive Mode'
  • Disabled Adaptive QoS and Traffic Analyzer (if in the case this was affecting the router's performance and eating up too much processing power).
  • Upgraded Asuswrt-Merlin to the latest firmware available for the ASUS RT-AC68U (384.18).
At this point, I am running out of options on what may be causing these internet issues. I have had this router for nearly seven years, but it runs just fine for me and my speeds, and aside from these intermittent internet issues, it is an absolute champ, but I am worried if this may be a sign of the router going bad on me? Or could there be other steps I can do to resolve these issues?

I am not entirely ruling out this being an issue with Comcast either as these issues started up around the time when I switched my internet plan to using the Comcast Modem (ARRIS TG3482G) as I was previously using my own modem, but with this new "promotion" from Comcast, it was nearly 50% cheaper if I use the modem they provide so I figured it would be no-brainer. But of course, there is a fee Comcast charges if they send a tech out to your home and resolve an issue that is related to your own setup and not something that is their fault, so I am hoping I can resolve the issues here unless it really does make sense to have a tech come out.
 

QuikSilver

Very Senior Member
For the last five months, I have been having intermittent internet issues where my internet slows down to an absolute crawl, to a point where it is unusable and is insanely slow. This requires either rebooting my modem (Comcast Modem, ARRIS TG3482G which is set in Bridge mode) and/or my router (ASUS RT-AC68U running Asuswrt-Merlin 384.18). At first, I thought it was an issue with my power levels and the overall signal coming through Comcast, but I have noticed that the ranges are in the acceptable range from Comcast (though a bit on the higher side, but these levels have been pretty consistent for years). Though recently, I have realized a faster way to resolve these intermittent internet issues/slow-downs that doesn't require rebooting the modem and/or router, but instead simply logging into the Asuswrt-Merlin configuration page and doing the following steps:
  1. Click on 'Network Map'
  2. Next, click on the Globe icon
  3. Click on 'Internet Connection' toggling it to 'Off'
  4. After a few seconds later, I click on 'Internet Connection' and toggle it back to 'On',
Doing these steps somehow resolves the internet issues now, without having to reboot my cable modem nor the router. Of course, it does take some time for the next episode of the internet slow-down to appear requiring to re-do the steps mentioned above. Another thing I would like to also note is when I do the steps above, or a reboot to resolve the internet slowdowns, accessing the modems configuration page (and not the router) via '10.0.0.1' does not appear to load immediately, but it takes 30 minutes to an hour for it to become available. No idea why this may be the case. I have tried quite a few things and even tried to dig through the logs but there is nothing that really shows why these issues may be happening. Some of the things I have already done are:
  • Switch my DNS servers to Quad9 (9.9.9.9)
  • Set my DHCP query frequency to 'Normal Mode' from 'Aggressive Mode'
  • Disabled Adaptive QoS and Traffic Analyzer (if in the case this was affecting the router's performance and eating up too much processing power).
  • Upgraded Asuswrt-Merlin to the latest firmware available for the ASUS RT-AC68U (384.18).
At this point, I am running out of options on what may be causing these internet issues. I have had this router for nearly seven years, but it runs just fine for me and my speeds, and aside from these intermittent internet issues, it is an absolute champ, but I am worried if this may be a sign of the router going bad on me? Or could there be other steps I can do to resolve these issues?

I am not entirely ruling out this being an issue with Comcast either as these issues started up around the time when I switched my internet plan to using the Comcast Modem (ARRIS TG3482G) as I was previously using my own modem, but with this new "promotion" from Comcast, it was nearly 50% cheaper if I use the modem they provide so I figured it would be no-brainer. But of course, there is a fee Comcast charges if they send a tech out to your home and resolve an issue that is related to your own setup and not something that is their fault, so I am hoping I can resolve the issues here unless it really does make sense to have a tech come out.
I had internet problems that I was able to track down to being an issue with the ISP. The router system uptime showed it being up for long time but I noticed that if I rebooted the router it seemed to resolve itself. Once I went down the rabbit hole I started looking at the owned modem I had. Thinking the issue was the long in the tooth modem I purchased a new one, but as you can imagine I still continued to have the same issue. (old modem needed to go as some channels no longer worked). What I was able to find out was that every now and then the modem would reboot trying to fix itself. Thanks to Conmon I was able to see that the internet was going out numerous times. Sometimes 16 times a day...Finally got a competent support person on the phone and they were able to help me push the issue further up the chain and found out the issue (node) was for my whole neighborhood (surrounded by older generation people who could care less about internet really). Long story short keep digging into it until you find something you can use to help them or yourself narrow down the issue. Check the signal levels, check modem uptime....does it sync with router uptime, then check and google search any errors you may get in the event logs for that modem.
 

darkgiants

New Around Here
I had internet problems that I was able to track down to being an issue with the ISP. The router system uptime showed it being up for long time but I noticed that if I rebooted the router it seemed to resolve itself. Once I went down the rabbit hole I started looking at the owned modem I had. Thinking the issue was the long in the tooth modem I purchased a new one, but as you can imagine I still continued to have the same issue. (old modem needed to go as some channels no longer worked). What I was able to find out was that every now and then the modem would reboot trying to fix itself. Thanks to Conmon I was able to see that the internet was going out numerous times. Sometimes 16 times a day...Finally got a competent support person on the phone and they were able to help me push the issue further up the chain and found out the issue (node) was for my whole neighborhood (surrounded by older generation people who could care less about internet really). Long story short keep digging into it until you find something you can use to help them or yourself narrow down the issue. Check the signal levels, check modem uptime....does it sync with router uptime, then check and google search any errors you may get in the event logs for that modem.
I appreciate you sharing your experience! I will not say I am an absolute expert when it comes to modem technologies, but can I upload my signal levels and readings from the Comcast modem here to get an opinion? Right now with the steps I have already completed, I am still 50/50 on whether this is truly a Comcast issue, or something wrong with the router I have right now.
 

QuikSilver

Very Senior Member
I appreciate you sharing your experience! I will not say I am an absolute expert when it comes to modem technologies, but can I upload my signal levels and readings from the Comcast modem here to get an opinion? Right now with the steps I have already completed, I am still 50/50 on whether this is truly a Comcast issue, or something wrong with the router I have right now.
Sure, I can only compare to what mine are. If anything it may give you enough to ask in the Comcast support forums.
 

darkgiants

New Around Here
So random update...

I had a power outage for a couple of hours earlier this morning, and after the power came back up, the internet was not working at all. I then noticed on my ASUS Router admin page (MerlinWRT) there was a message of "Your ISP's DHCP is not functioning properly". I was absolutely clueless as I didn't tinker with any of the settings to cause this issue as it was just a two-hour long power outage. I decided to give this a shot figuring it's giving me a DHCP issue to tick the option to enable "Mac Cloning", and instantly my internet is back online. It has been less than 24 hours so I can't confirm if this solved my problems, but any idea why the "Your ISP's DHCP is not functioning properly" messaged appeared randomly? I was thinking maybe with the long power outage, Comcast assigned a new IP address to the xFi Gateway Modem (that Comcast provides), or is it something else? The logs really aren't helpful on both the router side and modem to confirm what went wrong here.
 

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