Strange RFI/EMI problem with self-made amplifier


2010-10-05 10:35 am
I have built my first stereo chip amp using a Sanyo LA4227 IC for two 3W speakers.
The speakers sound well, but whenever somebody turns on/off any switch in my house (even in other room), annoying popping sound occurs in both of them, which increases with volume. What could be possibly be the reason? Poor grounding/shielding? Any help will be much appreciated.

P.S. I did not have access to a PCB so I made the circuit only by soldering the points with short copper wires.
add an RF filter to the input of your amplifier.

What feeds your amplifier? It too may need an RF filter.
The speaker lead terminals also need an RF filter.

Particularly troublesome interference equipment will need suppressing at source. These are anything with a motor inside.

Post a schematic and a pic. There may be an instability in your amplifier that is responding to fast transients and exaggerating what comes out to the speaker.