We had a Mobi Panache, same issue. Dumped it in favor of a Galaxy Nexus and never looked back. That may be our last HTC handset since they never seemed too interested in fixing the issue... in fact, they wouldn't even acknowledge the issue existed.
Oh yeah, and the Panache was unable to receive MMS messages as well. Instead, we would just receive a message that stated "A Media has been removed", in multiple languages. Seemed to be an issue directly related to the Panache which we were never able to resolve.
Robellusilicity Screw You