Just had the issue with the 4 blinking tone leds, so I stumbled upon this forum.
A factory reset (hold volume button and tone during power on) worked fine. The problem appeared to be related to a recent change I did in program A. I updated it with a patch containing no preamp (amp > clean > no amp) and I turned most other things off as well, like compressor, eq and delay. Stored this patch again in A and the '4 blinking leds' problem returned. Then I saved the 'no amp' patch to nr B (because I would like to have this patch), and that seems to work fine. So, it looks like program A is not allowed to have a patch without an amp ? Weird ...
