It's highly recommended that you upgrade your SX10 to CE8.x which fully supports Proximity.
TC7.3.2 is also subject to some security vulnerabilities, and this version has been deferred as well. If you're going to stay on the TC software train, you should upgrade to at least version TC7.3.6.
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Just as a general comment/update - as of July 2016, the Proximity 2.0 client is released. This significantly improves pairing performance on Windows. For most laptops, it is no longer required to fiddle with settings for "microphone effects" etc.
Please update the client to the latest (http://proximity.cisco.com) and open the Proximity app window. While the window is open, we use the microphone in "exclusive mode", by-passing many of the problems we had on Windows earlier.