I have heard that any attempts to upgrade the sound system in the 2010 X5s, X6 and X5M will result in a VERY loud chime/gong sound that cannot be disabled. Have any of you heard about this? Does anyone know if there is a solution? I currently have a fantastic upgraded sound system in my 2005 X5 (focal speakers and subwoofer, Audison amps, etc) and was planning to transfer these to my new X5 ordered with the basic sound system. However, this information has me worried and I have heard it is nearly impossible to bypass. BTW, the "gong" volume control in the new X5 X6s will not work when a new amplifier is placed. Thanks much for your input.