note added to build instructions

README.adoc

@@ -510,6 +510,10 @@ the actual build process.
 To build the project, there must be somewhere a recent https://github.com/raspberrypi/pico-sdk[Pico SDK] and
 the environment variable `PICO_SDK_PATH` must point to it.
 
+NOTE: I'm most of the time on the master branch of TinyUSB which is part of the Pico SDK.  Originally
+TinyUSB 0.15.0 is being used by Pico SDK 1.5.1. +
+So if you experience unexpected behaviour, I recommend to update TineUSB and retry. 
+
 If you want to adopt YAPicoprobe options to your needs, check CMakeLists.txt and invoke cmake accordingly.
 
 Requirements: