Thanks. The hiss is common in many of the last generation Sony prosumer camcorders, my TRV-900 among them. It’s only really noticeable in a sit-down interview with a lav. I figure it at 10 kilocycles but when I filter it out I lose the highs on the voice. Leave it as is and I cringe at the playback in a theater situation. I can send the unit to a service that will disable the offending internal pre-amp but then I would need an external pre-amp to replace it. That makes it a $500-600 option for a five year-old camera. I also considered the minidisc workaround but was under the impression that I needed a second tabletop unit for better playback into my Mac. Is this not the case? Am open to any and all suggestions.