Dont know whats wrong with my new Xperia Sola. Am from using it with Vodafone GSM network. All of its features and functions are working fine but the only problem am facing is while making or receiving calls. Until i remain on WCDMA, the call conversation use to be good but as soon as i switch to GSM mode the interlocutor just cannot hear me (i can here him clearly). I checked all settings and call options but nothing helped me yet. Can any one of you help me out in this ? Thanks for any help in advance.