When I crank my car up my amp comes on but plays at 10% volume for first few minutes then randomly will kick up to normal set volume. Amp's power light is on, all wired connections double checked and good. (Note) I have the sound input running through an external high level output converter. Now the weird thing, if I ground the high level speaker wires for a second the amp kicks right into normal playing and will continue to play from that point on with no volume issues.