The customer has had some Valcom horns in place and working fine for years. Paging and BGM are fed into a V-2001A page control. Just one zone, no talkback.

Recently we added 8 more horns in a new addition. Since there were so many horns and it was a couple hundred feet away from the V-2001A, I added an additional VP-2124D power supply for the new horns. The audio pair was connected to the output of the original controller with the existing horns, and sent out to the new addition. There, the new power supply was connected to the power pair of the new horns.

In this configuration, the new horns did not work. No BGM, no page. If I connect the audio pair to the addition directly to the BGM source, the new horns work fine. There just is no paging going to the new horns.

I replaced the V-2001A controller with a new one. No change. Any thoughts on a next step?

Thank you.
Jim