8 pin DIP dual 16-bit DAC (digital to analog converter) #TDA1543
Regular TDA1543 (no 'A' suffix) is an I2S input format. TDA1543A is Japanese time multiplexed input format
If the sound is distorted, the most likely problem is the TDA1543 (U26) chip. This sounds as if the volume is very over modulated and is “clipped”. Be sure to use the TDA1543 version and NOT the TDA1543A
Stern #100-5018-00
Location U26 on Stern Whitestar MPU/Sound boards