I have an Airport Express connected to my stereo via 1/8" to rca cable that I use to stream from my Apple devices. I have an ipad air 2 and an iphone se and my wife also uses an iphone se. I recently noticed some distortion when playing certain songs and at first attributed it to the amplifier. The distortion mostly occurs on female vocals...kinda a cruchy, crackly overlay on certain frequencies. It happens on both channels, so that got me tjinking it's a source issue. I plugged some earphones into the AE and sure enough, thats where it's originating. Now the strange part, it only occurs when streaming from the iPad to the AE. If using either iphone to stream to the AE, no distortion. I plugged the headphones directly into the ipad and again, no distortion. Anyone have this isssue before?