Hooking up a Klipsch

This is receiver thermal going in protect issue and has no bearing to your sub, The sub has its own power amp and not supplied by the receiver. Thermal module may be bad. See a tech.

Just use one of those jacks. Then turn the frequency select dial all the way up. This will work just as well.

I had the same problem. Dont know why the receiver set it up this way but grab your remote, go down to the lower right and select ch setup. Keep on pressing it till your receiver says SW. Then press lev+ on your remote to change the db on your powered sub.

Hissing? How loud? A sub isn't even capable of making high frequency sounds at normal volumes.

The Pioneer manual would tell you how to enable and test the subwoofer output.
Page 17 and the MACCV procedures on Page 33 (auto) or 43 (manual)

Yes, go to your menu then setup then speakers then subwoofer, it's probably in "LFE" it should give you the option of Sub, LFE, or Both. that should do the trick. Also check the crossover point and season to taste. While your at it; there should also be a setting for speaker level, toggle down to sub and adjust the sub out level, it's probably at it's minimum setting. Hope this helps

if using a sub out cable to a powered sub,you have to go into the reciever menu and turn the sub out on

Just need to register, login and you can download manual from here.
It will take only two minutes.
Hope this helps.

Here's how I'd do it... connect the subwoofer pre-out to one of the unused analog inputs (CD or CD-R perhaps?). Turn on Zone 2 by pressing the MULTI-ZONE ON/OFF button. The MULTI-ZONE indicator will light.

Press CONTROL. (Zone 2 should display) Use the INPUT SELECTOR dial to select the source for the zone you have selected. In my example, CD or CD-R.

Of course, you'll need the sub hooked up to the Surround back speaker terminals.

Here's a link to the manual online:
Pioneer VSX-1018 Manual

Things to keep in mind:
The Surround Back setting must be set to ZONE 2. See page 41 of the manual.
The volume level going to the sub will probably need some tweaking. Check out page 7 to see how to manually adjust volume levels, or get it close by adjusting the Master Volume while in Zone 2 control.

I'm not sure if the auto setup function (with the included microphone) will work properly with this setup. And, of course, this is not a "suggested" setup by Pioneer, so please use caution when hooking everything up.

Good luck!

problem with connection

I got the same issue. But, I go ahead hooked it up two banana plugs on teh VCR outlet. It works fine on my Cerwin Vega Sub.