The Bluetooth phone support can be troublesome due to the ambitious nature of what we're trying to accomplish on a PC. It's never going to be perfect, but we can try to make it more stable. Remember, we're counting on many devices: (Sound card, PC audio driver, Bluetooth dongle on PC, PC stack (BlueSoleil), your handset, and its Bluetooth stack) to play nice together.. something Bluetooth does not do well (play with others). That said, the best solution can be trying a different Bluetooth dongle. For some reason, the best one are usually the cheap off-brand model from MCS - http://www.mo-co-so.com/USB-Bluetooth-Dongle-for-Centrafuse-Auto-p/mcs-usb-btd.htm or http://www.mo-co-so.com/Miniature-Class-2-Bluetooth-Dongle-p/mcs-btd-min.htm. Both work well for a lot of people. More expensive name brands like Kensington, D-Link, Belkin are generally not as good. Stay away from those, unless you already own one and want to try it.
Other things to remember, is that the connection issue are going to happen. Its Bluetooth. Get used to removing completely the pairing from both the phone and the PC when you have an issue. It's the only way to cleanly re-create the pairing. When you remove the pairing from PC, remove it with CF closed, from BlueSoleil My Bluetooth Places on the Desktop. Unpair and delete the device from BlueSoleil; then do the same on your handset. Then restart both your PC and your handset. Then start CF up, go in Phone Settings and use "Search for Phones" in CF Settings to re-create the pairing.