Strange WHR-600D Mbps speed drop

[abaximan]

Howdy,

I have Buffalo WHR-600D with fresh factory version of DD-WRT (v24SP2-build 23392). It work perfectly, that is, till around 8pm to 10pm everyday. Around then download speed drops from 50/20 Mbps to less then 10/20Mbps. I reseted ISP modem, my router router, PC and nothing happens. When I connect directly via ISP modem/router I get normal speed. After a 2-3 hours everything goes back to normal. I already did hard reset, reinstalled original non DD-WRT firmware and then back to DD-WRT.Is there any setting I'm not aware of? Could it be some hardware problem?

[abaximan]

This problem is getting me crazy
Firstly...I got new router from shop. And absolutely nothing changed, so I don't believe it's malfunction anymore. At more or less same time bandwidth slowdown occurred again. I did play around with different setting and this is what I find out.

1. Speed slow down happen every day at more or less same time. It usually starts from 6-7pm and lasts till around 10pm.
2. Reseting any device won't do poop.
3. Reverting back to factory setting, reinstalling original software or reinstalling DD-WRT again won't do poop.
4. Slow down seems to effect only internet speed as browsing various urls, watching you tube etc., but not p2p. I stopped all torrents, closed utorrent and checked speedtest and it was something less then 10Mbps. After that I started to download torrents, just random ones, whichever had more seed and download got almost to 3,5MB/s which is more or less around 35Mbps.
5. If I connect more devices (I connected one more over cable and 3 more over wifi) and start speed test with all of them simultaneously, they get close to 10Mbps...so altogether I'm getting right speed.
6. Right after I applied some firewall settings (Block Anonymous WAN Requests and Block WAN SNMP access and probably some other too - been a long day) speed actually rise to normal, back went back down after maybe 30 seconds.
7. I connected both PPPeO and DHCP - all the same. Which is weird though....I can connect to PPPeO while ISP modem in not in bridge mode. I'm more or less newbei, but I did some home networks in my time and I never seen that before Smile

Right, I almost forgot. I did test local network speed but I can't tell this reading is good or bad.

High Performance Timer: 0.0000003289

Test File: \NW_SpeedTest.dat
Write Time = 0.0195761 Seconds
Write Speed = 8,173.2226720 Mbps
Read Time = 0.3095341 Seconds
Read Speed = 516.9059600 Mbps

Test File:\NW_SpeedTest.dat
Write Time = 634.6486017 Seconds
Write Speed = 25.2108000 Mbps
Read Time = 872.4217236 Seconds
Read Speed = 18.3397520 Mbps


So hopefully any one could provide me with solution one of this days?