I have three different HD television sets, all connected through the Scientific Atlanta Explorer 4250HD boxes via Component Video and Analog Audio cables.

All three sets exhibit the same issue:

I cannot change the set-top box's volume via the 4250's remote control.
I can change the STB's volume via the buttons on the front of the Explorer box - a pain in the butt because I have to get outta my seat.


(I can also control the actual television's volume control...but I am trying to consolidate on remote control usage.)

I already have set "Audio Control" to "Variable."

I noticed that before I "forced" 720p (via the "Info + Guide" Wizard setup), the STB volume was controllable through the 4250's remote. Once I manually "forced" to 720p, volume control disappeared.

After doing research, someone hypothesized that the STB only controls analog audio - explaining why it's not change-able. I deem this incorrect as I am able to change it by pressing the buttons on the front of the box.

I've done a lot of research on this topic but have not been able to find any answers. Any help would be most appreciated!

I cannot change the set-top box's volume via the 4250's remote control.The manual states the default volume control settings on the remote control is TV volume control - change it back to the STB!
D. Program the Volume Controls.
By following the steps below, the user can
program the volume controls (Volume Up, Volume
Down and Mute) . The default volume control
settings on the remote control is TV volume
control. If you wish you can control the volume via
your CABLE box, use the following steps.

STEP1 Press the [CBL] button and the [SEL]
button simultaneously for 3 seconds.
The iO button will turn on.
*Tip : The iO button will light on for 20 seconds.
The next step must be entered while the
iO button is on.

STEP2 Press the [VOL +] button.

STEP3 Press the [CBL] button.
The iO button will blink twice to
confirm the programming.

Thank you, sir!

The manual states the default volume control settings on the remote control is TV volume control - change it back to the STB!
D. Program the Volume Controls.
By following the steps below, the user can
program the volume controls (Volume Up, Volume
Down and Mute) . The default volume control
settings on the remote control is TV volume
control. If you wish you can control the volume via
your CABLE box, use the following steps.

STEP1 Press the [CBL] button and the [SEL]
button simultaneously for 3 seconds.
The iO button will turn on.
*Tip : The iO button will light on for 20 seconds.
The next step must be entered while the
iO button is on.

STEP2 Press the [VOL +] button.

STEP3 Press the [CBL] button.
The iO button will blink twice to
confirm the programming.