Thanks to @Protonerd and thanks to @JakeSoft - for letting us know about the issue.
Got home from work and checked out the library for this annoying reset() call..
I first thought I could just set doReset = true to false in the .h file... but it didnt seem to work.
I commented out the line in the .cpp file I think its working. (so this is good info to share)
I have reset a few times, and do -not- hear the pop any more.
I have lowered the volume previously.. but will do more tests, and raise the volume
For others who may be using the default DFRobot library:
file:
DFRobotDFPlayerMini.cpp
part of this method/function:
bool DFRobotDFPlayerMini::begin(Stream &stream, bool isACK, bool doReset){
line#:
103 (I believe)
this line: (comment it out)
//reset();