Question to the Hyperion 0610i charger

I've try my Hyperion 0610i charger today, and try to charge a FlightPower EVO25, 5000mAh, 4s pack with it. Set the charge current to 5 amps and start chargin process.
During charging, i've take a look at the screen and see the current drop to "0" for few second and then return to 5 amps.
It did it during all the charging process, so i don't take a chance and End the charge before the end.

Do they have guys here how have the same charger and experiment the same thing?????

Or this is normal on this charger??
Thank you!

David