Help using integrated as power amp

I bought the 747 because: one, I wanted to be able to use it for watching movies and two, the input selector on the arcam doesn't work anymore. It will work for a while and then the sound will just drop out. When I spray deoxidizer on it that helps but never solves the problem. I was thinking of buying a NAD C275 power amp and running the front speakers off that. Do you think that will improve the sound quality from the 747 or do you think my best bet is to buy another integrated(used). Unfortunately, my budget for that would be less than a 1000, ideally even less than that, as I want to first buy a totem storm sub and center channel.

Thanks for the help Unfortunately, the only switch is for AV operation or normal operation. As far as fixing the switch I asked two places and they both said it would probably be a few hundred dollars. Having said that I have only listened to the totems through the arcam once and although I liked the dynamics/energy(my terminology may be faulty)the highs seemed harsh compared to the NAD. I am going to try this weekend to rehook up the totems to the arcam - I live in apt in NY and my wife is sick so trying it out right now is not an option. I might post this on the home theater section since my interest is 50 50 but I am wondering what people would do to improve this system if they had 2500 to spend. I should say I listen to mostly rock and most of my music is digital. thinking of building a music server with a mac mini.

Do you think adding a NAD C275BEE power amp would help the NAD 747 or is it solely the preamp section that you see as the problem. Not sure if it matters but I will almost surely never progress beyond 3.1 - thanks