Toshiba TV Ant-1 connection problem?

Toshiba Projection TV, model TP50H60

I started to notice that I maybe had a warm-up problem with my Ant-1 connection. Sometimes it took a while for me to get a signal and to view the TV normally. While this was occurring I noticed that when I “switched” to video 1, turned on my VCR and got the feed that way, that I had a perfect picture. So this was my “initial” bypass method. When I hooked the ‘cable’ wire to the Ant-2 connection, I got a perfect picture every time. So it appears that there is an issue with the Ant-1 connection. This would be O.K. except that I have “PIP”, and I really like it and use it often. PIP, as a normal function, does not work when set to Ant-2. While troubleshooting, I connected the ‘cable’ wire to Ant-2, noticed that the initial ‘hookup’ goes to a ‘box’ and out of there to the rest of the TV. So, I “temporarily” swapped the Ant-1 & Ant-2 wires, coming out of the rear of the box. I still had a perfect picture, and I now had a “partially” functioning PIP. That is to say, the PIP “picture” was showing that there was “no signal”, but, when you actually tried the swapping function of the PIP, it did work and you had a picture. So, it seems to suggest that I need to try and replace “this” junction box.
If you think that I am on the right track, can someone suggest a “name” for this “junction cable box” and also where I might be able to buy one. Basically this box has the “3” cable connections, for Ant-1, Out and Ant-2.
Thanks in advance and any assistance,
Eddie