ATTiny is generating PWM based tones with 32kHz sampling rate. Then I've created R-2R DAC and then trying to amplify it for speaker. However, LM386 is sinking signal from R-2R. If I don't connect LM386 then there is signal on DAC output. How to correct this circuit?
Also I'm planing to make low pass filter, to filter out PWM hiss during playback and some white noise during silence. But I will open separate question for that.