Strange wifi problem

Hi there,

I'm having a strange wifi connection problem with a MacMini running 10.6.8.

It is connected to the internet via wlan using two identical AVM Fritzbox 3030 wlan routers.

One of these is connected to a DSL line, the other is used as a repeater and the MacMini

connects to the second one and has worked flawlessly until recently.

Now I frequently experience a very slow connection to the internet (Safari, Firefox, Software

Update, ftp). The strange thing is that everything works fine on two accounts on the

computer (one admin, one standard) but not for three other ones (one of them newly created).

First I thought, it might be a Safari problem, so reset Safari, emptied the cache, also

repaired permissions, all to no avail. I checked the logs for any new/unusual entries and

didn't find any. I checked that the connection is fine by connecting a MacBookPro, that

had continuous decent transfer speed.

The airport connection icon in the menu bar of the Mac mini shows 4 bars, connection to the repeater

is good (transmission rate of 54, RSSI of about -50 to -60), but if I try to ping the router

connected to DSL from the slow account, I get frequent packet drops and sometimes ping times

of up to a few seconds. If I switch to one of the unaffected accounts, ping times immediately

go down. If I leave the shells running the ping open in both accounts and switch between

accounts I can see that ping times go up when I'm using the affected account and go down

when I use the other one.

I really have no idea why the basic internet connection would be affected by any personal

settings, but maybe someone can enlighten me. Otherwise I'd probably go for a fresh install,

but I'd at least want to get an idea what is causing this odd behaviour.

Thanks in advance!!