I am currently using an AVOTEC communication system and e-prime software (as well as a "STIM" system and software) for audio stimulation. There is some bleed-through from one channel to the other and I need to generate pure stereo sounds. Does anyone know of better equipment to use for this, or how to solve this problem? Everything seems to be fine until the tubing connections which lead to the patient. I cannot get a good enough seal to block the sound from the second channel completely. I am having a terrible time with the NEUROSCAN equpiment as well, and am currently bypassing their audio stim box.