This is my first post and I have a million questions. I hope some kind souls out there will not mind my noobness and be able to guide me any way they can.
Firstly, I have a headphone amplifier circuit that runs off 9v using the TDA2822M chip. The amp works fine as a mono amp (yes i know class D no good for headphones) but that is all i need for my purposes. My question is in regards to the nasty 'thump' I get when I switch on the amp. Is there some kind of capacitor/resistor combination that I can use on the input voltage that powers the circuit on slow enough to minimise the thump in the earphones?
Secondly, I have redesigned and enclosed a digital wireless transmitter/receiver, connected it to a headphone amp and built myself a nice little cheap digital earphone beltpack system. My issue is with the digital noise that is part of the circuit. I also have a great deal of noise when nothing is connected to the transmitter input. I know this probably sounds a bit vague but unless I post pictures and describe in great detail the whole setup (which I can do) it may or may not help with the issue. I have powered the transmitter circuit with a linear regulated 5v power supply. I have used a 10k 1:1 transformer on the audio input. I am suspecting its a shielding issue somewhere. Any advice or questions for clarification will be much appreciated. Please let me know any specifics you might require to be able to answer this question. I know there's probably so many variables and I am not experienced enough to know where to start more than what 'google' has suggested. Kind regards..