Tuner connection and sound variance. HELP

Time and time again I'm told by fellow Audiogoners to trust my ears.This one has me perplexed. I recently got a Yamaha CT-1010 tuner and I like it but have a minor concern. If I play my CDP with the tuner on there is interference and the CDP doesn't sound as good. I can understand this as I suppose the tuner would be introducing RF into the system. But what I've noticed is that if I unplugg the interconnects of the tuner from my preamp, even though the tuner is off, the sound is even better. Does it make sense for my CDP to sound better when I unplugg the rca's of my tuner's interconnects from the preamp even though the tuner is off?
Thanks for your help. Oh yah, I just got some Totem Beaks and the sonic improvement is obvious. I bought them with the attitude that all I could loose was the investment of the Beaks but was pleasently surprised.
It could make sense if your pre-amp is less then perfect. Maybe the inputs are influencing each other? I don't know if you've got some spare inputs, but it could be worth using inputs that are as far away as possible. Or try to borrow another (pre-) amp to see if that will make a difference. If it does, maybe it's time to shop around for a new pre.....
What your describing isn't that unusual. Your tuner and all that's attached to it may be acting as an antena, maybe picking up more than broadcasts too. This is one of the reasons that some like "purist" hair shirted pre's that only allow one input at time.
Is it possible when I get my Magnum Dynalab MD100 that the problem I described above will be resolved or am I likely to experience the same phenomenom?
Just thought I'd mention that I recieved my MD100 and the problem no longer appears to be happening however I am using different shorter interconnects.