Why thread make my function running slower?

Question

I'm currently coding a macro software where it records mouse movement, click and keyboard input. I'm using Tkinter for the GUI and pynput to detect input. So, in my gui I have two buttons, one for playing the record and one to record mouse and keyboard inputs. When i press record, i have to re-click on it to stop the record. But, pynput function loop make my Tkinter GUI freeze, so i set a thread to make my Tkinter window working while pynput function are running. The problem is when I stop the recording and then I play it, the record is 0.5x slower than the moment i was recording. I think it's because of time.time(), which is imprecise because of the thread. I'm actually blocked and i don't know how to fix this.

import threading
from tkinter import *
from tkinter.ttk import *

from macro import startRecord, stopRecord, playRec

# Window Setup
window = Tk()
window.title("MacroRecorder")
window.geometry("350x200")

def startRecordingAndChangeImg():
    global stopBtn
    recordBtn.pack_forget()
    stopBtn = Button(window, text="stop", command=stopRecordingAndChangeTxt)
    stopBtn.pack(side=RIGHT, padx=50)
    threading.Thread(target=startRecord).start()

def stopRecordingAndChangeImg():
    global recordBtn
    stopBtn.pack_forget()
    recordBtn = Button(window, text="record", command=startRecordingAndChangeTxt)
    recordBtn.pack(side=RIGHT, padx=50)
    stopRecord()

# Play Button
playBtn = Button(window, text="play", command=playRec)
playBtn.pack(side=LEFT, padx=50)

# Record Button
recordBtn = Button(window, text="record", command=startRecordingAndChangeTxt)
recordBtn.pack(side=RIGHT, padx=50)


window.mainloop()

from pynput import mouse, keyboard
from pynput.mouse import Button
from pynput.keyboard import Key
import time
import os
import json

mouseControl = mouse.Controller()
keyboardControl = keyboard.Controller()

def startRecord():
    global start_time
    global mouse_listener
    global keyboard_listener
    global macroEvents
    macroEvents = {'events': []}
    start_time = time.time()
    mouse_listener = mouse.Listener(on_move=on_move, on_click=on_click, on_scroll=on_scroll)
    keyboard_listener = keyboard.Listener(on_press=on_press, on_release=on_release)
    print('record started')
    with mouse_listener, keyboard_listener:
        mouse_listener.join()
        keyboard_listener.join()

def stopRecord():
    mouse_listener.stop()
    keyboard_listener.stop()
    json_macroEvents = json.dumps(macroEvents, indent=4)
    with open(os.path.join("C:/Users/***/Desktop/autre/python project/macro-recorder/data/test.json"), "w") as macroRecord:
        macroRecord.write(json_macroEvents)
    print('record stopped')


def on_move(x, y):
    global start_time
    macroEvents["events"].append({'type': 'cursorMove', 'x': x, 'y': y, 'timestamp': time.time() - start_time})
    start_time = time.time()


# I use the same methods for each listener on_click, on_scroll, on_press and on_release, I reset the timer to 0

def playRec():
    print('record playing')
    for i in range(len(macroEvents["events"])):
        time.sleep(macroEvents["events"][i]["timestamp"])
        if macroEvents["events"][i]["type"] == "cursorMove":
            mouseControl.position = (macroEvents["events"][i]["x"], macroEvents["events"][i]["y"])
        elif macroEvents["events"][i]["type"] == "leftClickEvent":
            if macroEvents["events"][i]["pressed"] == True:
                mouseControl.press(Button.left)
            else:
                mouseControl.release(Button.left)
        elif macroEvents["events"][i]["type"] == "rightClickEvent":
            if macroEvents["events"][i]["pressed"] == True:
                mouseControl.press(Button.right)
            else:
                mouseControl.release(Button.right)
        elif macroEvents["events"][i]["type"] == "middleClickEvent":
            if macroEvents["events"][i]["pressed"] == True:
                mouseControl.press(Button.middle)
            else:
                mouseControl.release(Button.middle)
        elif macroEvents["events"][i]["type"] == "scrollEvent":
            mouseControl.scroll(macroEvents["events"][i]["dx"], macroEvents["events"][i]["dy"])
        elif macroEvents["events"][i]["type"] == "keyboardEvent":
            keyToPress = macroEvents["events"][i]["key"] if 'Key.' not in macroEvents["events"][i]["key"] else special_keys[macroEvents["events"][i]["key"]]
            if macroEvents["events"][i]["pressed"] == True:
                keyboardControl.press(keyToPress)
            else:
                keyboardControl.release(keyToPress)

I'm expecting to have mu GUI not freezing and pynput function working on his fullest.

Thanks in advance for you responses.