I just purchased a used XT-245 and the 8" interior speaker barely had any sound coming out of it. So I figured the speaker was blown. I replaced with another 8" speaker which produces a little more sound but not much. You have to lay on the floor to hear it unless you turn it up but the 2 small speakers are 90% louder. I've played around with all the settings in the stereo and no luck. Just wondering if this is normal for this model? Thanks