When using the SMH10, I find that after a call, it invariably continues with a clicking noise for several seconds after the call has ended. There are also other clicks and ticks that I hear when it should otherwise be silent.

Also, when using earphones, while a connection is open (intercom or SatNav instructions, music from iPhone etc) there is a high level of background hissing .this cannot be from the Bluetooth connection since being digital, it will be silent when it should be. So this is being generated by the SMH10.

Why is it generating so much hiss and how evan this be reduced or eliminated?