The use of the badge up-side-down and pressed to the face (like a mobile phone) is frowned upon - this is because of acoustic shock issues (from the loudspeaker) and the likelihood of overdriving the Mic due to closeness to the mouth.
For the next release of badge why not add either a button or accelerometer to allow the badge properties to be changed when used in this manner i.e. damp both the Mic and L/S to mobile phone levels when the badge is inverted?
This would allow users to hold the badges closer to their ears/mouths and get over many of the issues of using the badges in noisy environments.
I appreciatee that this may be going against the initial 'idea', but users do and will continue turning the badges up-side-down when privacy is required, or in noisy environments.
This request has previously been made at numerous user groups.