Very simply put. I can't use star codes before putting in the dial number or extension. If I setup the star code in a line key along with the extension to dial. It works. If I do it on hook or select the line first I get invalid number.
Didn't care too much prior to today but now I really need to figure this out. I only have this problem with obihai phones.
After all this time I finally figured it out. I changed the ITSP digitmap line and added |*xx| to it.
Now, I can dial star codes.