I have the Shaker audio without navigation.
I had an issue where my car audio would no longer connect with my USB media or my Bluetooth audio. I originally thought it was IOS 8 on my Iphone but my wife's zune did not work either.
I tried master reset, and many other things I read on the web but the only thing that worked was disconnecting the negative terminal on the battery for 20 seconds. That finally reset everything and everything is now working correctly.
Just thought I would save share and save someone the same trouble I went through!
Thank you was having same issue
2014 mustang 5.0, side louver, fp8 package, recaro race seats
My mods: BMR lower control arms and relocation brackets, koni yellow adjustable struts, steeda heavy duty mounts, steeda panhard bar, steeda sport springs, Flow master outlaw cat backs, air raid synthamax cold air intake, SCT x4 tuner with Bama tunes, black emblems, black GT fuel door, illuminating door sills, raxiom smoked fog lights, 3.73 gears, JLT oil separator, GT 500 spoiler, MMD hood struts...