Use the acronym of M.A.I.N. (Mindfulness, Attitude, Insight and non-clinging) towards mindfulness of wholesome emotion can lead to development and maintain these beautiful states of mind such as generosity, lovingkindness, compassion, joy, happiness and wisdom.
Mindfulness of hearing is one of five practices of mindfulness of Six Sense base. This practice can ground us by anchoring our attention apart from preventing unskillful states of mind from arising.