Like previously mentioned it probably all has to do with cost, but if they are cutting corners there, where else are they cutting corners? I personally won't buy a detector that doesn't come with an adustable volume control, but that is just me. You can make up the difference by buying headphones with adjustable vulume controls on each earpiece and the afore mentioned mono-stereo switch. They can be found for under $50.00 incl. shipping if you shop around at the various dealerships, but can be quite warm in the summertime when it may be necessary to go with light-weight headphones.