Wiring problems

Not certain if HDMI can be used in a setup like this. I'd try it from the home theater (HT) to the TV, and other wiring for the other components.

For video:
All of these should have component connections (Y/Pr/Pb). You'll only need the video cables for each device:

• Video out from cable, HT, and combo player.
  
• Video in to TV. Your choice of inputs.

For audio:
Hopefully, the two output devices (the combo player and the cable box) have digital audio (fiber optic, or RCA coaxial). Otherwise, you'll only get stereo sound. VHS is stereo only anyway.

• Audio out from cable box and combo player.
• Audio in to HT.

The TV won't have anything to do with audio in this setup. Alternatively, you could try hooking up all inputs to the TV, and connecting audio out from the TV to the HT. Works best if this connection is digital, for surround.