GT-BE98 - 1GB fibre download keeps dropping to 4 or 5 Mbps

[ice70]

Hi,

My GT-BE98 has been running fine for a few months, but this morning I was getting about 4 or 5 Mbps instead of the usual 750+.
Connected my laptop directly to the ONT and got the expected speed.
Reconnected via the router and the speed dropped down to 4 or 5 Mbps.

This is on wired not WiFi.

I am at a bit of a loss on how to resolve this and any suggestions on what to look at would be gratefully received. I have tried rebooting 🙂

Firmware Version : 3.0.0.6.102_37839-g83af1c6_1208-g0311b_BB0B

thank you.

[jzchen]

You wisely already tried the first thing I would have suggested, which is to restart...

Is the upload speed terrible also?  (Still trying to think/research what could be the cause).

[jzchen]

Did you try a different LAN port, with same/similar poor speed?

[Saltgrass]

Did your ISP provide you with a Gateway/modem?  Your Wi-Fi speeds are normal?

Did you get any recent firmware updates which might be involved with your situation?

[ice70]

Upload is solid and unaffected when ever this happens.

No ISP provided hardware - but direct cable connection to ONT showed significantly faster download speed.

The last firmware update was: 2025/05/17

Wifi was also showing slow speeds, but WIFI can be a bit temperamental, hence the more significance attached to the wired connection speeds.

Unfortunately for testing / resolving this problem, whatever caused the slowdown has now currently stopped and I have a fast download speed once more. I have no idea what caused this slowdown.
It is the second time it has happened, last time was almost exactly one month ago.

The odd thing is when I connected via a VPN, I had a much faster speed than without.
Not as fast as the direct connection to the ONT, but faster than without the VPN.

When this happens again, I'll connect my laptop to another port and test once more.

thank you

[ice70]

ok, scratch that... slow speed is kind of back.

I connected the laptop to once of the 2.5GB ports and got a download speed of about 750!

Tested my desktop on the 10G port and got 4, moved to the connection to the 2.5 port and got about 6... so could there be a problem with the desktop windows 11 connection?

BUT, wifi is also showing up a slow, 5G - 2 is usually my faster on, and 2 or 3 m from the router, I am only getting 8Mbps, whereas I was getting I think 400 or 500+ previously.

[jzchen]

Could it be a hidden/background download like Windows update taking up bandwidth?  For example if the desktop is slow then plug in the laptop to that Ethernet port and quickly test download speed, does speed resolve?  Kind of suspect that if both Ethernet and WiFi show same slow speed but other device is (more) normal.

[ice70]

 I don't think there is a large amount of traffic while doing these speedtests.

I loaded up the GT-BE98 web admin and kept an eye on the dashboard network traffic, which for the most part was under 1MB and mostly under 100 or 200 KB.

Ran the speedtests this morning while everyone else was asleep:

laptop
WiFi 6g: 543 Mbps
WiFi 5g 2: 481 Mbps
wired 789 Mbps

s21 ultra:
WiFi 5g 2: 4 Mbps [laptop test after still reporting 472 Mbps] [restarted the phone, but had the same results]

Desktop (windows 11):
wired: 5 Mbps

Both the S21 and Desktop have shown speeds closer to those of the laptop in the last month.

Took a look at the client list / network and all the wired devices are not showing any Tx / Rx / access time figures whereas the wifi connected ones are.

[jzchen]

Just an FYI but the client list has seemed to be inaccurate, hard to explain how and don't know how it affects the traffic monitoring...

To clarify please the normal speed does return on S21, Windows 11, on the slow Ethernet port, and WiFi?

[jzchen]

Do you have anything connected to the USB 3.0 port?  (If you do as a test move it to the 2.0 port).

What are some possible sources of noise (that could affect speed)?  (USB 3.0 HDD is one.  I've removed mine and reported to a friend who works at ASUS).