Definatly a satatite problem if it is saying loss on tuner 1 or 2.
Couple of questions
how long are you coax cables??
What kind of cable rg59 or rg6???
Satilite signals should be on rg6 but will work on rg59 for short distances.
What is your signal stringth if you are under 70 your satilite is probably not pointed well
Do you have other recievers???
Check signal stringth with another reciever on the cable that is going to your TiVo.