What is the ruling on reciting aloud in supererogatory prayers during the the day, such as the Duha prayer, if it increases one's devoutness?

The preferred method for daytime supererogatory prayers, according to the consensus of jurists, is to perform them silently, with the exception of the eclipse prayer (kusuf) and the prayer for rain (istisqa'). None of them recommended vocalizing prayers like the Duha (forenoon) prayer or similar ones. Rather, their texts explicitly state the desirability of performing them silently. Some even considered vocalizing them during the day to be disliked (makruh). It has not been narrated that the Prophet (peace be upon him) vocalized the Duha prayer or any other daytime supererogatory prayer. If you vocalize a daytime supererogatory prayer, there is no sin upon you, but you would have missed out on what is superior.