If you have aaa configured:
If so:
aaa authentication ppp NO_AUTHENT none
int async 1
ppp authentication NO_AUTHEN
The function of "autoselect during-login" provides the username/password combination WITHOUT having to press Enter when initiating character mode sessions (Terminal window after dial for example). That is why it doesn't resolve your issue.
If you have "aaa authorization network" configured, you will need to disable this for the async port as well using the list method.
If you don't have AAA configured, remove the ppp authentication statement from the async interface.
Keep in mind, character mode sessions on this interface will have to type in "ppp negotiate" or the short command to start ppp on the line. You could add this to circumvent it:
int async 1
autocommand ppp negotiate
Hope this helps.
