We are VoIP company based in Latvia specialising in multimedia streaming over SIP/RTP protocols. This year we optimised our SIP stack for Symbian OS and it is already implemented in two of our products. One of them is push-to-talk application. Now we have decided to advance this product.
The last two months we have been looking for information on how to enable duplex audio on NOKIA 6630 and 6680 mobile phone models so that audio playback would work along audio recording simultaneously. Sadly, this feature is not documented but we know that these cellphone models are capable of concurrent audio in/out.
Here at TiVi (Latvian acronym for Tilts Visiem) we have made numerous attempts to contact NOKIA, but so far unsuccessfully.
We would like to know your opinion or any references. Is it worth to join Forum NOKIA Pro? Although it costs 4K EUR, we are considering this option if we can get detailed documentation or support.