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2pH devices...2pH values reading (..long..(:...)

Hi All.

I have an pinpoint pH probe attached to a Neptune controller.This pH device
works for more than 1 year.
Few weeks ago I bought a pHep device from Hanna.
When I use to read the pH parameter I always had different values.
I made several calibrations with both probes, many test..but same result.
here some of readings on different water parameter.

First, I did calibrate BOTH devices with brand new calibration solutions at
both values 4 and 7.
Then I took water samples in an clean recipient, so I could avoid any other
sources of electrical or whatever could affect the reading.

Water source      pHep     Pinpoint     TDS         KH test kit
Planted tank        7,3          6.86           200ppm    70ppm

Breeding tank     6.4          5.77         80ppm         20ppm

Osmosis water   5,8          5,06         <10ppm     <17ppm

TDS (total dissolved salts)is an electronic reading device from Hanna
 KH test kit is Aquarium Pharmaceuticals.
The pHep device is new. To be able to read the pH value I do have to wait
about 3-4 minutes so the probe should show the value w/o any  changes.The
pinpoint device (1 year old) does stabilise in max 2 minutes.

Both devices does calibrate OK and remain that way.
The reading differences are only when I need to test the water pH.

I do know that the pH probes do get old and they go off one day...So,
logical the pHep device should read OK and my old pinpoint has gone
crazy.........But as the readings I do think the old probe is more accurate.

Any suggestion are welcomed.
I am very confused about this matter.