A thermo-electro sub-assembly comprises a gas supply, a first duct, a first heatsink adjacent a first device, a second duct, and a second heat sink adjacent a second device. The hearing aid housing further holds a socket adapted for receiving a programming connection in order to connect the programmable signal processing device to an external programming device, and a switch adapted to be operated by the hearing aid user, and a cover arranged above the socket and switch and pivotally linked to the hearing aid. The protective line separates the aluminum from adjacent silicon-based layers. A hub is rotatably coupled to the outer rotor motor and has a first portion disposed within the motor housing and a second portion disposed outside of the motor housing. If a data block is missing, the network node retrieves the missing data block over the mesh overlay network via a pull mechanism.