HalSteel

I'm very new to MixPad so I would be grateful for simple. I record a track (like the Drums) that works great but when I try and add the bass (or anything else) the track I'm listening to is recorded along with the new part. I have played with the headphone switch (next to FX) and know it has to be in ASIO. I do keep getting a message that im running things through a MIDI filter. If ou can help a lost soul I would be grateful.