i just want to take a few minutes to sum up the facts... there is a lot of information here and for someone new to this it might be a bit overwhelming.
1. All AR9331 based routers suffer USB 1.1 to USB 2.0 interoperability problems.
2. when purchasing routers from a single vendor some routers fail immediately, some routers work perfectly, some routers work some of the time. For example, I have 11 alfa AP121U routers here 5 of them fail immediately 5 of them work perfectly and one of them works some of the time.
3. the problem is somehow related to WiFi. When you disable the WiFi the problem goes away.
4. The problem can be resolved in every single case by using a passive USB 2.0 hub
5. The problem only happens with USB bulk transfers. Isochronous transfers seem to be OK.
6. the problem is not a power supply issue
7. this is not related to the place of manufacture of the chipset (happens with both korean and taiwan made chips) or version.
did i miss anything?
(Last edited by lsoltero on 13 Dec 2012, 16:26)