I face similar problems on an Asus Notebook with AR928X wireless card. The connection to my router is extremly unstable, after about a minute the connection drops every time, and re-connecting takes an awful lot of time. I tried using WICD instead of Network manager - same problem. I have Windows installed on the same notebook, and wireless works fine there, so it's no hardware failure.
I face similar problems on an Asus Notebook with AR928X wireless card. The connection to my router is extremly unstable, after about a minute the connection drops every time, and re-connecting takes an awful lot of time. I tried using WICD instead of Network manager - same problem. I have Windows installed on the same notebook, and wireless works fine there, so it's no hardware failure.