Unable to Adjust Sound with HDMI

Using a Scientific Atlanta Cable Box 8300 HD. Attached to HDTV with A HDMI cable from Monoprice.com.
I am Unable to adjust the sound from cable box. I tired the Variable Audio Setting, HDMI Audio Out.
But the cable box volume control has no effect. I was told that its because its hooked with HDMI cable.
Is this true ?Thanks

Most likely the cable box only can adjust analog audio. Digital audio is bitstreamed directly with no processing. That’s why there’s a volume control on the TV.

Thanks… Its j ust that the volume is very low on the TV on many channels.
Thats why I was looking for a way to adjust the sound from the cable box.