Howto:SAMwin: Potential problem with media negotiation

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SAMwin's job is doing media-relay between the caller and the operator phone. To easily forward RTP (to avoid transcoding) SAMwin tries to negotiate same audio codec on both call legs (incoming from caller and outgoing to operator phone).

We have seen cases where this almost worked, except for the packet size/rate. SAMwin requested 30ms packet sizes, we offered 60ms. In this situation, SAMwin endlessly tried to negotiate equal packet sizes. This only happens when there are LOCAL CODER settings the innovaphone configuration. In this case, we enforce the packet size set in the local codec configuration.

The problem is easily fixed by adjusting the local codec config to identical values on all innovaphone devices, so that both call legs on held by SAMwin always use the same packet size.