I guess I'm lucky. I've had this phone since July 18th and have used the aux with external speakers at work often with no issues. It sounds great. I did install VIPERANDROID FX but had no issues before or after the install. The usb charger cable is always plugged in when I use the external speakers. I'll try it without the cable to see if there's a difference. Won't be able to do that until Tuesday because the speakers are at work and I'm not going near that place until the Holiday weekend is over.
Update: Tested aux without usb cable and have no issue. Working fine.