Mike, welcome back. I'd agree that as long as you can get adequate sound level that you don't have to worry about "over-extending" the 3803 with a high setting on the volume control. The volume control is a variable resistor that changes the proportion of voltage from the MP3 that's let in to be amplified. At the maximum setting essentially all of the voltage is let through, and a setting nearly that high may be necessary with some players that have a relatively low output voltage. So, applying a high volume control setting doesn't strain the 3803 in any way, it simply lets in the needed amount of voltage for the required sound level.
