Download speed has decreased to one-tenth

[maxim123]

Hello, I think it happened since few days ago, I am not sure if I am infected or not since I don’t use any antivirus and do regular scan or such, the last scan I did was couple months back I think.
Yeah, so since few days ago, I noticed my download speed has decreased to one-tenth. I checked the speed by trying downloads from couple sites like sourceforge or filehippo. The speed I used to get was above 2mbps (my bandwidth is 20mbps), now it has decreased 220 - 310kbps.
Download from test speed sites(the sites which gives you files to download to test your download speed) works with full speed though.

I am not sure what’s going on. The isp guy checked but they just kept on trying to test the download speed from those testing sites which gives full download speed.

Could my windows be infected?

Thank you.

[maxim123]

I found there being differences in server speed as well, when I view youtube videos, the bandwidth is used fully, but in other sites, only a little bandwidth is used and the download speed gets to the speed of 220 kbps.

[Bruce]

what sort of monthly plan are you on?
have you used up the monthly quota perhaps?
what is your broadband connection type; ADSL, satellite, cable, wireless etc.
does anybody else in the house share the bandwidth?
what is your OS? if Win10 and you have no 3rd party AV then the internal Defender is just fine.

[maxim123]

what sort of monthly plan are you on?
have you used up the monthly quota perhaps?
what is your broadband connection type; ADSL, satellite, cable, wireless etc.
does anybody else in the house share the bandwidth?
what is your OS? if Win10 and you have no 3rd party AV then the internal Defender is just fine.

20mbps unlimited plan. It is ADSL. There are few who use wifi but I have checked during the time where they don’t use wifi, and it is the same (they don’t use much internet at all, just check emails and that’s it). It is win10 and I was using just microsoft defender, installed avast today to scan for virus but it found no virus. (should I uninstall avast or keep it?).
the isp is also saying they are checking from their side, but it has been few days now, so not sure when they will finish ‘checking’.

The inbuilt download speed in web browsers (firefox & chrome) is especially slow, so I have stopped using them.

[Rustys]

Have you attempted rebooting the modem and router?

[Bruce]

and the inbuilt Defender protection is all you need.
I ditched Nortons about 5 years ago since Defender has been scoring as well or better than the big paid-for boys.

[maxim123]

Have you attempted rebooting the modem and router?

and the inbuilt Defender protection is all you need.
I ditched Nortons about 5 years ago since Defender has been scoring as well or better than the big paid-for boys.

Thank you both. It is solved now, the isp finally sent the fiber cable guy and they found the calibration or something of my fiber cable was off and they repaired it. It is working good now.
I will uninstall avast then and just go with defender.

[Rustys]

Thank you for letting us know @maxim123.