We have a Swisscom Davos. I cannot see how this phone could be connected to a Jabra headset, although there are numerous headsets on the Jabra compatibility list for this Swisscom Davos. The Davos has only one RJ11 connector. Can anyone tell me anything about this? Additional question: We are a bit torn between the Pro 920 and Pro 925 (in the latter case, the option of connecting to a mobile phone). Is bluetooth really strong and stable enough as a transmission standard? Thank you for your feedback.