SPA1001 Dialed Digits Becomes Doulbe Digits. Please help.

[sihan6256]

I just set up my SPA1001 to register on Sipsorcery with Sipgate and GV. Everything is working except a very weird symptom. When I call a number and asked to enter an extension or passcode, every digit I entered becomes double digits. For example, the entered passcode is 12345 and the phone interprets into 1122334455.

Could you please help? I would really appreciate it.

Best Regards,
Linda