no output sound

I was advised to turn on “Software Playthrough” but when I do that I get the echo problem again. And when I put the recording on iTunes and try to play it back there is very little volume, even though the output meters are showing a good record reading, about 8 db and the waveforms are maxing out even to the point of clipping. My HP 5750 is automatically setting the volume levels to their lowest settings which I take to mean my input is so high that I could damage the sound card. While I am recording I am getting good volume both on my headphones, add-on speakers, and internal speakers, just no volume on playback.

Is this the same problem as here:
If so, please read the replies there and if you have further questions about the same issue, respond in that topic.