Buzzing IC's

Tried that too. I'm using some inexpensive unshielded IC's now that have no issues but they are way to long. 

Looks like the sub has a "ground lift" switch on it?  Does that matter if it's on or off?

Thanks! I thought that would be it. I tried a cheater plug on the subwoofer and the preamp. no difference. Crazy! I give up. 

If your sub has a 3-prong AC plug, use a cheater, (3-prong to 2-prong adapter) to see if it breaks the ground loop.

I tried a pair of Tara Labs directional cable now. Same buzzing as with the WBC Cables. Unshielded cables no issue. I should lift the drain on the Tara's.

Had a similar problem with an AV receiver. Was a ground loop issue. Are the subs and pre amp plugged into the same circuit?

I've tried them in both directions on my subwoofer and amps with the same results. They work fine between my DAC and preamp. I'm baffled to say the least!

Just a thought here.  Are you following the Arrow markings of the cables?  Signal flow From-To.  On the Source, preamp side, the cable Shield and Signal Ground wires are connected together.in the rca  On the subwoofer side connector, just the Signal wires are connected in the rca.  The shield is not connected.

It’s the second set of cables reacting the same way. I’ll try one at a time and pushing in farther if possible.

Try connecting one cable at a time and see which one buzzes. Sounds like a defective cable. 

@cetla416,

Example, look like these?

Are the IC cable RCA plugs hard to push onto the RCA jacks on the ARC LS25?

Looking at the plugs they look like they would be.

Just a guess you are not pushing the plug(s) all the way onto the RCA jacks on LS25. Center pin of the plug is not making a good contact with the center contact of the jack. Try pushing harder to make sure the plug center pin is seating correctly into the jacks female hot signal contact.

RCA.

No, I have the 2549 with the metal Amphenol connectors.