Hello Jean-Philippe,I've found the following info in the rc-505 manual troubleshooting section, perhaps this is your problem?
'Sound is missing from the beginning and end of the recorded track''To prevent noise, a fade-in and a fade-out are applied at the beginning and end of a recording. In some cases, it may sound as if some of the sound has been left out.'
Nevertheless I wouldn't hesitate to contact Boss/Roland support, just make sure that you have the newest firmware.
Regards, Michał W dniu 11.02.2017 o 09:58, Jean-Philippe Rykiel pisze:
Hello dear loopers,just bought this device, had read the manual before and really thought It would be the holy Loopers Grail, Since repeater to never made it.Here is my issue.I want to make a continuous, non-rhythmic, loop, with pad like sounds. To avoid bumping effects, or phase differences between the beginning and the endof the loop, I start by recording a two second or more silent loop.Then, I switched to overdubb and record my pad or whatever with a slow attack and a slow end so there is no abrupt point in the wave form. The result is a smooth loop with no audible click. This Is an old technique I'm sure everyone here knows, and it worked perfectly on the RC2/20. with the RC505, a bump is heard at loop start no matter what I do, from the moment overdub is engaged. Before I take it back to the shop, does anyone have an advice for me other than, "take it back to the shop" ?