E250 Certain tracks would lose right or left channel any time.

Can hve over 500+ songs on the player, randomly during any track you would lose left or right channel Big Time w/ Lady GaGa on Sansa E250 w/ Raphsody subscription. I communicated w/ there tech rep's "?" if thats you would want to call them. I deleted the tracks & cache, reload the track again as it still does the same symptom. Seems like a total wash is going to rectify this problem.