I really don't know why people keep thinking that reinstalling will help - it won't.
OK, then you'll have to be more precise and list your equipment (which Mac, which OS, which Logic version, how much RAM, how many disks, how much free space on your startup disk etc).
How are you buffers set in Logic Pro>Preferences>Audio>Devices>Coreaudio?
Also you say "when I play something" - what do you mean? You play an instrument and record the audio? Or you use the qwerty keys for MIDI? Or something else?
Also, you say "slow to respond", but could you be more precise? Does the meter respond within, say, 1/32 note? Or does it take a second (that's a lot) or more?
Do you have the latest compatible drivers for the One (if those are needed) installed?