I just ordered and received a used Yamaha THR100HD, sold and shipped by a larger distributor on Reverb. The unit arrived defective. It has a baffling anomaly on high single notes. It manifests as harmonics or overtones, almost like a Hammond organ playing in the background. I can manifest it at will. I can and will return it, but the box had something peculiar written on masking tape. It says DEMO AS. Now I know what demo stands for, but what does anyone suppose AS might stand for or mean? I'm wondering whether AS means something to those in the retail or distribution side of things.