Zoiper IAX & SIP softpthone (previously known as Idefisk) is a VoIP (Voice over Internet Protocol) client application, meant to work with Asterisk and SIP-capable IP-based communications systems and infrastructure. * STUN support * Various codec support * Multiple accounts * Adaptive Jitter buffer * Echo cancellation * Multilanguage support * Portable storage device support ZoIPer IAX & SIP softphone supports the following languages: English, German, French, Spanish, Dutch. It is available for Windows, Mac OS X and Linux.
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sometimes crash, without any reason
nice sip softphone