Strange battery cell readings

Hardware Other Hardware
1

Morning Folks.

I have the following hardware.

Supermate DC6 Balance charger
Gence Ace 400mah 5s 45c battery
And 2 x voltage buzzers

At the end of a balance charge the Charger will indicate the cells are charged to something like this 4.19, 4.20, 4.19, 4.19. 4.20

When I connect the 2 voltage buzzers the readings display something like this. 4.24, 4.17, 4.20, 4.18, 4.19

Which one do I believe?

2

As confucius said

Man with one meter always knows the correct voltage

Man with two meters never knows the correct voltage

The only way to be sure is to get a certified Multimeter and then check which is more accurate, although I would always suspect those cheap voltage buzzers