I don't think you can switch between the two, more info [link=http://www.modemsite.com/56k/buy.asp]here[/link]
"If your modem is set-up for the V92 standard, and disconnects after displaying 'You have ignored an incoming call message', you will need to reset the modem to the V90 standard. ..... Open the 'Control Panel' and select 'Phone and Modem'. Click the 'Modem' tab and highlight your 'Modem'. Click 'Properties' and then select the 'Advanced' Tab. From here, you should see an 'Initialisation Command' field. Enter AT+MS=90 into this field and then click 'OK'. " Courtesy of Wanadoo customer support, :good: