The Yealink T28's now have a "Prefix" button option. So I have set one button to prefix *9 I have another key set as an extension 303 But I cannot use them together. If I press the prefix button I get the *9 but when I press the BLF button it erases the *9 and just dials the extension. If I press the prefix button and manually dial the extension, it works just fine. Is there a way to use the prefix button with the BLF button? I have emailed Yealink but I thought I'd post while waiting for a reply. Thanks!