Even the command example tell's that the maximum is 15 I am not able to exceed the level 14: n22 /proc/acpi/ibm # cat volume level: 14 mute: off commands: up, down, mute commands: level <level> (<level> is 0-15) n22 /proc/acpi/ibm # echo up > volume n22 /proc/acpi/ibm # cat volume level: 14 mute: off commands: up, down, mute commands: level <level> (<level> is 0-15) Reproducible: Always Steps to Reproduce: 1. 2. 3.
This is a known problem. I have reported it upstream back when 0.11 came out.