I make a call with an SPA962 (most likely going over an InPhonex SIP trunk) to various companies and their auto-attendant asks for various numbers (you know the drill, "for sales, press one" or "please enter your account number now"). I dial, I can hear the DTMF tones, but the other end ignores me. Occasionally, it works, but most of the time, nothing. This is really frustrating because I then have to use my CELL phone to make the call. Sad when a phone system can't be used to make a call. Anyone got any fixes?