Alot of things play a factor in this....

When you dialed in your tone you probably dialed it in with headphones. Your head phones and studio monitors probably have completely different freq. response.

I am not sure what kind of head phones or studio monitors you are using. If you are using your pod primarily with your studio monitors then you should really dial your tones in while listening through them. Think of it this way. If you dialed all your tones in while plugged into a 4X12 cab and then switched cabs to a 4X10 cab it is going to sound completely different. you always need to dial in on what you are listening to the most.