Since [this button requires special styling](https://github.com/bmac/gaia/blob/adec66499c0834ad04e6c11d70f1b3becd263ba4/apps/clock/style/timer.css#L102-L109), either the `id` will have to be `timer-menu` or (better yet) that CSS declaration's selector will have to be changed to `#timer-sound-menu`.