windows 10 system running REW 5.20 with UMIK1. I cannot get any true SPL readings while playing test tones. The SPL meter reads the sound level of the room, in my case around 37DB. If I speak or play music in the room the SPL meter shows the increased volume of the room. Running basically default settings in REW ( Java , UMIK1 microphone). I first tried hooked up to my Marantz 7013 and then just tried running output to my laptop speakers. same results. Looking for help as I must have something configured wrong.