This has never caused me any problems but has baffled me for ages. My Pioneer Ax5i receiver is usually set between -15 and -20 on the volume control and this is very loud. Any higher than -15 is just too loud. But my hifi amp is usually set to +40 or above. So is my AV volume set correctly, or should that also be in the +db range. Why is one -ve and the other +ve?