I just made a call through pennytel using the speed dial. Around 4 minutes on the modem, but pennytel charged me for over 7 minutes. I made a 3 second call using a dial plan and pennytel charged me 3 seconds. I rang my own mobile and made sure I didn't hang the mobile up for a while. Then I made the same call through the speed dial and didn't hang the mobile up for about 50 seconds. Sure enough got charged for the 50 seconds. Fixed lines don't have the same problem when testing on my pennytel timed account.
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Voxalot speed dial call not terminating - Other Provider - Voice over IP - Whirlpool Broadband Forums