Supersedes Technical Service Bulletin Group 91 number 11-20 dated October 21, 2011. Customer may report that cracking, grinding, rattling, humming, whining, or similar interference is coming from one or more speakers. Parts of the speakers (such as the brackets, cables, or covers) or parts of the interior fittings (such as door covers, rear shelf, facings, or covers) can vibrate at certain frequencies, causing noises. The radio tuner or other control modules may be affected by electromagnetic interference from aftermarket electronic devices.
