I cannot make *67 work when I use my GrandStream GXP2000 phone. *67 works fine on my softphone, so Asterisk handles *67 correctly, but it doesn’t work with GrandStream phone.
I am sure its because the GXP2000 supports *67 call feature and it tries to handle the caller id block internally without passing the *67 digits to Asterisk.
[SOLVED] In GrandStream Account setup page, there is an “Enable Call Features” option that can be turned off.