I'm having a very similar problem... I too have the altitude problem where it's going up... I adjust and it levels off then it starts to loose altitude... it does't seem to hover well while maintaining altitude... the other problem i have is that say that i am in a hover and i push the copter into forward movement... I start loosing altitude again... the only way around that is if i do amazingly minute movements on the joystick for forward movement...

Oh yeah... I also have a servo that twitches or goes crazy sometimes... Only seems to be the one that controls my movement to the left... I'm new to this so let me explain it this way... if you are looking at the remote its the joystick on the right... and the servo the flips out is when i push that joystick to the left... It literally twitches for a second or two... It also twitches sometimes when its on the ground with the throttle down... say just before i take off or after i land... which i'm sure it probably means that it twitches in flight and that might also be affecting the fact that i have to readjust the remote nearly everytime i'm in flight so it'll stay straight...

I love this little copter and it's already provided me with hours of fun... But seeing all the videos out there of what people are doing with the CXs as far as just running around... I'm not talking about acrobatics or anything like that... Just ease of flight... It just doesn't seem possible with the way mine is acting... Could i have broken something that might be affecting it... I've replaced everything visible that was bent, broken, or chipped just to make sure...

Kind Regards,
Hakan