2011 Toyota Matrix Owners Manual - Page 244
2011 Toyota Matrix Manual
Page 244 highlights
3-2. Using the audio system Type B STEP 1 STEP 2 STEP 3 STEP 4 Press Press Press . (MORE). (ASL). Press that corresponds to the desired mode (LOW, MID, HIGH or OFF). ASL automatically adjusts the volume and tone quality according to vehicle speed.