I am making a audio amplifier using tda2030 or tda2050. It will connected to my raspberry pi and will be on 24*7. There is a continuous hum noise when i connect it to Pi but no noise when connected to mobile. Please suggest me a way to eliminate the humm. And is there a way to keep the amplifier in a sleep state unless an audio signal is received because keeping it always on will heat it up significantly. These are the circuits i will be using. And i would power it with 5V (most preferable)or 12V.