Removing the metadata in audacity works, the zero crossing thing should not be something to worry about.
Have you tried testing the default files?
The default files work better, but make the same click.
I used audacity function in menu select-at zero crossing on the hum sound, now the loop of the hum is ok without click.
Tomorrow i try to use the same function on every files and I hope to fix the problem.
When I export files in audacity the meta data windows appears before saving file. Tipiccally I use the clear button before save file. This is enough for save file without meta data or there is something else to do?
Sorry I didn't check back sooner - sounds like you have found the Audacity function to move to the nearest zero-crossing point (and then clip up to that point) - this is necessary for any sounds that loop, an for any sounds that are part of unmixed fonts where the sounds are chained together otherwise you often get a nasty click like you describe. If you imagine the waveform as a continuous cycle if you don't have both sounds that meet with a zero crossing then it makes a 'jump' which causes the click (unless you get lucky).
Metadata click issues usually are at the end of the file (where the card tries to play the metadata as if it is part of the sound). If you clear them in Audacity then it clears all metadata as far as I can make out. I have had files in the past that had a metadata click, but had no visible metadata in Audacity. Used Audacity to clear the metadata (as you describe) and that fixed the issue. Also you can tell it has removed invisible metadata as the exported file will be a few bytes smaller.
I used the zero corssing select to correct the hum and lookup clicks, the only sounds that are looped and I solved the problem.
In my sound bank all the swings are mixed with the hum sound in the background, so I have the swing sound at the beginning of the file and then the hum sound continues for 90 seconds. I used the normalization filter on all files to correct the DC offset and added a fade in of 0,2/0.5s at the beginning of the swing and a fade out at the end of the 90 seconds of hum.
By doing so in the clash sounds I managed to solve all the artifacts.
Unfortunately in the swing there are some clicks that are heard sometimes and do not seem related to one or more sund in particular.
This bug did not manage to solve it.
On the PlecterLabs website there is a guide that says that the files should be exported in unsigned WAV 16b mono, but Audacity cannot export in unsigned 16bit format, the only format is the signed 16 bit.
Could this be the problem?