My printer is H-bot with Bowden extruder. Have problem on Smoothie. Looks like it micro drags before retract so I have blobs right on retraction points :(
Migrated from arduino/ramps on Marlin and doesn't have that problem on it. It seems like Marlin retract little bit earlier or doesn't stop ont retract points. Can't explain it correctly.
Tried different firmwares, change accelerations in config, retraction speed in slicer and always the same blobs on retraction points. There are no other problems.
whats your retraction length set to? may just need to turn it up as you need more retraction with Bowden and all software will behave a little differently.
It's not retract length or speed problem. Tried 3-15mm and 40-200 mm/s, all the same result. Write again - same slice settings (or G-code) on Marlin don't give blobs.
Though if you find something it's likely it'll just be random/un-reproducible.