1. A hearing aid, comprising: a microphone; a speaker; and a processing unit coupled to the microphone and the speaker, wherein the processing unit is configured to obtain a signal, obtain a measure that corresponds with an adjustment made by a user of the hearing aid, and determine a signal processing parameter based on a feature of the signal, the measure that corresponds with the adjustment made by the user, and an adaptation parameter, the adaptation parameter being a tuning parameter that controls whether to put more weight on new information or previously obtained information when determining the signal processing parameter; wherein the processing unit is configured to determine the signal processing parameter using an adaptation algorithm that gradually adjusts the signal processing parameter over time.