Zofo,
You may have a dead S-10 amp; they have been known to fail.
I have an S-10.
If you have not already done so:
Check your LFE cable
Check your AVR’s OSD to make sure the sub is enabled.
One rather easy test to isolate your S-10 as the problem would be to:
Turn the S-10 amp off.
Turn the level to Min.
Unplug the LFE input.
Plug in a male-male RCA cable to the S-10 input.
With the S-10 set to Auto or on, and the Level turned to Min touch the center pin on the free end of the RCA cable. This will induce a 60 HZ tone to the Sub input.
Slowly turn up the S-10 Level. You should hear sound coming from the Sub but if the sound is barely audible you probably have a failed amp.
I just tried this to see if it would work and it does. Your body’s resistance will affect the level of input by this procedure so that is why I say to turn the level up from Min slowly.
Aperion may be willing to work something out for you once you determine the amp is the problem even if the amp is just past its warranty period.
Jack