Small, but annoying audio drops

Hello,

instead of my 2010 MacBook Pro which works basically very fine with Logic Pro 10.3.0. (but to slow for some PlugIns) I use now a brand new iMac 2017 Pro 4,2 GHz Intel Core i7 with Sierra 10.12.6 and Logic Pro 10.3.2.

Quite unlike as expected my new system has a lot of minor audio problems. If I work with Flex or use the fade-tool or move audio parts, I have very annoying audio drops. The sound stops for a while or I hear some small glitches.