1. CPU clock signals modification. Cost $50 The sound systems DMA is clocked by the 16 mhz CPU clock. With some software such as digital audio or video recording, it is possible to get a disturbance on this clock and causing the system to lockup or bomb. Also it causes noise on digital outputs or problems with SCSI harddisks writing huge audio files.
2. Audio quality modifications: Cost $100 i) Remove the bass boost on the output so to obtain a flat frequency response across the entire audio spectrum, ii) reduce the internal speaker amplifier gain so that the speaker output is limited, it is benefical on some software where volume control is inaccessible, and iii) reduce the input gain by 10dB, this brings the input level down to exact line level.