I would like to use QoS on the WL-520GU (flashed with USBTomato EXTRA FW 1.28 tomato-NDUSB-1.28.8748-Ext) since I have a Linksys VoIP (SPA-2102) phone.
Before activating QoS, SpeedTest.net indicate 4.38Mb/s (download) and 0.64 Mb/s (uplooad). I then run Easy Toastman QoS setup (Tools> System), paste the lines, and press execute. In order to be conservative, I set QoS at 70%, that is 3Mb/s (download) and 0.45Mb/s (upload).
When I test the line quality with PingTest.net, I get approx. 6% packet loss, 33ms ping and 5ms jitter (Line quality D, MOS: 3.90). These data are quite consistent when I do several tests (packet loss being between 4-6%). These packet losses lead to a severe deterioration of my VoIP calls: the person who calls me cannot even hear me anymore.
When I turn off QoS, everything resumes to normal, then I get 0% packet loss, 31ms ping and 3ms jitter (Line quality A, MOS: 4.39). Again, these data are consistent when I do a retest.
Needless to say, the router works perfectly with TomatoUSB (many thanks !!!!), apart when QoS is ON.
Is somebody having the same problem ? What is the solution ?