Some problems with new C450IP

Hi there...
First of all i am sorry but i can only write in english....
I have not found an english forum....

I have just bought a C450IP set, and i have some problems/issues....

The phone works fine, but i think that the problems is in the BASE-station....

I can not configure the Base from the phone with "Menu > settings > Base >" the handset just jumps out of the menu again when i push "OK"....

An other problem is that i can not select if the handset should call via IP or PSTN with long/short push of the call-button....
It always select IP.....
I can recive calls from both PSTN and IP, no problem there.....

At last it seems like there is an issue with G711a and G711u, i get a lot of noice (bzzzzzz) when selecting these, my provider support both G711a and G711u, and also G729, and when i use G729 i have no problems....
(I have a 512/512 connection and nothing else is connected...)

I have updated the base to the newest firmware avalible, so i think that should be ok.....

What can i do ??

I have tried to connect to the base both with and without any cables connected, i have tried to pusch paging button, and many other things, but i can not connect to the base at all.....
Can i do a hardware reset of the base in some way ??

Pleace, if you can help me, i would be really happy.....

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Kind regards
Peter

Hi there.....again.....

I found the Factory-reset, and now i can connect to the base.....
(the one with turning the base off and on with the blue paging button pushed...)

Also now i can use both IP and PSTN connection to outgoing calls.....

The only issue i have left now is that the codec still make a lot of noice if i use G711a or G711u.... i can not talk to anyone becource the noice is mutch louder.....

Do anyone here have fix for that ??

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Kind regards
Peter