Problem receiving audio from Android phone

I'm new to this Arduino DSP stuff, but I've read articles on how to make a music visualizer from various sites.

I've decided to route audio output from phone's 3.5mm left channel to arduino analog a0(Free running. ADCH 0-255). But, when i serial plot the values I get, it seems that there is no audio received, and the values just oscillate from 0-255 no matter which song I play, even when I play no song. I knew I had to amplify the audio before sending to analog in, but I decided just to watch how small is the signal so I sent to analog IN directly.

No, I don't have an oscilloscope yet.
and yes I have a mic, but I felt routing audio from phone directly to arduino would make life simple.

PS: there is so much noise, when I connect A0 to breadboard. Ive tried several serial capacitor combinations but output is just 0-255 oscillations like a sine wave.

Help me out,

Connect a 10K resistor from the analogue input to 5V. Connect another from the analogue input to ground. Finally connect your audio through a series capacitor, about 1uF.

Solved my problem!!!
Thanks Grumpy _Miken :slight_smile: xD