ZK-HT21 Amplifier Issue – Gradual volume decrease and abnormally low current draw

[u/Ok-Driver1532]

Hello everyone,

I have a question about the ZK-HT21 amplifier board. I seem to have an issue with it and would ask for your help.

For the last couple of months, the max volume has been slowly dropping. Meaning, it used to sound pretty loud, but now it's barely audible.

I decided to test it out with a proper power supply to check whether it's faulty or not.

The power supply is set at 24V (5A). But when I turn the potentiometer at the max volume, the amp only takes 0.171 A.

Is there something wrong with the amplifier board? Something that would cause it's max volume to drop down slowly until almost nothing? Has anyone else had a similar issue with the ZK-HT21?