This might be a long shot as I am very new to the XW-P1 and I'm not absolutely sure about your XW settings and external config... Perhaps you need to configure the Solo Synth Block & DSP setting then backup data/save for each tone you create with an external source before rebooting the XW-P1?? There is a relationship between Parts - Zones & MIDI External Inputs. There doesn't seem to be an option to save Mixer data to Flash storage or upload to PC, have you tried using the 'All Data' or 'Setting Data' backup setting?? Do you use an external sound block (MIN IN/INST IN jacks) as the Oscillator Block then apply it to the Solo Synthesiser? Normal DSPs - Can be saved and edited as a user DSP (see page E-37 of XW-P1 manual) - then reapplied to user made solo synth tones. Solo Synth DSP - Saved as part of the Solo User Tone Zones 2-4 played only in Performance Mode effect internal sound sources as well as external MIDI sources. 4 Tones, Master EQ, Effects, DSP configs are all saved into the 'Performance .ZPF' files. I don't really know what else I can tell you. Thoroughly read the XW User Manual. It confuses the hell out of me! There are settings for the DSP, but it depends what your applying them to, and if your keyboard is controlled externally via MIDI/virtual controller then maybe that will over-ride Mixer/DSP settings. I've not done much experimenting with the XW sadly. I find the unit a bit daunting, so I play the guitar instead. Hope this helps you in some way. http://www.casiomusicforums.com/index.php?/topic/6160-using-the-xws-resonant-filter-with-polyphonic-tones/ Good Luck!