Hello, my name is***** am an independent tech connected to you via this pay for assistance website service. Your satisfaction is my top priority and in return your positive rating is the only way I will receive credit for my time.
If your cable box is connected via HDMI
(or other AV cables), then you should just need to press the "INPUT" button on the Toshiba remote then choose the proper input (see back of tv to verify which input your cable box is actually connected).
If you need more help then simply REPLY back here and tell me what happened when you pressed the INPUT button AND which input your cable box is actually connected to on the back of the tv.
Before you go any further, please be sure to take a moment right now to click the positive rating so that I get credit for helping you today. Doing so does not finish or close the question or prevent us from continuing our conversation here. My livelihood truly depends on your positive rating.
Please do not click bad-poor rating if you are unhappy with your product. Doing that blames me for your problem, destroys my standing here as a professional, and does not issue you a refund. Instead REPLY back here.