Unexpected results with TDA 7052
Why are you using a 50 ohm speaker? The TDA7062 was designed for an 8 ohm unit.

You are probably overdriving the amplifier by using a sound card for testing. Try a few mV input.

Try putting a pot on the input, as a volume control. Sound cards have a low impedance output, so 10k (log) will be fine.

It's a high-gain amplifier and might be oscillating if you built the circuit on a breadboard. Put it on a PCB.

I've never had any problems with the TDA7052.