CD keeps playing on 2008 335xi, Logic 7

This is a Logic 7 system (std w/335 series).
When switching from CD to AM/FM for a minute or so, and I go back to the CD, the song on the track has advanced further into the track as if it has kept
playing on it's own (although I don't hear it because I'm listening to the radio). If I go to AM/FM for a longer period (like 5-10 min) then come back to the CD, it has advanced thru several tracks. Again, playing by itself, as if it did not pause when moving to AM/FM.
Switched back and forth between CD/AM/FM/AUX using the mode button on the right side of the steering wheel.
Am I correct to assume that the CD should stop where it is when you switch to AM/FM/AUX, until you come back to CD where it should pick up playing where it left off?
Possible software glitch?
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.