I found the solution for this Ableton issue. Ableton company is aware of this drift in time issue with hardware sync, and they put a hardware resync button. Hidden normally, but might be enabled in MIDI tempo settings. It is designed exactly to solve this drifting issue. From time to time during song playback, one can press on it to resync the external gear. I tried it with Quad Cortex tremolo / slice effect. It works fortunately. 
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