Hello. I've built FS on a CentOS 6.4 virtual machine (MacOS 10.8 Parallels) using minimal config for testing with Huawei K3520 dongle. It was initially unlocked (Vodafone DE) and voice enabled by default. Using manual USB port config all worked fine including calls and sms, voice quality was good. It uses USB2 port for modem, and USB1 for audio. I tried to attach 2 dongles, made udev rule and that worked fine too, however this scenario does not guarantee the same order in which dongles are seen after each reboot. Automatic device discovery does not seem to work with that dongle. I specified IMSI for each dongle, or IMEA, or both. Every time mod_gsmopen tries to use /dev/ttyUSB3 which is not a proper choice for those dongles. I can see K3520 in the list of supported dongles. Maybe something I do wrong. Any idea? Jo