Reading 1-wire not the same time

[klump4u]

First post here,
Yesterday i have update Domoticz to the stable 3.8153 its running on a Pi2 with Stretch.
Everything went ok and works good but i have one issue.
I have 3 ds18b20 sensors on GPIO4 but they dont update anymore at the same time, in the 'Hardware' tab i have set the Sensor poll periode on 60000 milliseconds (1 minut) and now sensor ''a'' update at 19:00:00', sensor ''b'' at 19:00:20 and sensor ''c'' at 19:00:40 and then ''a'' at 19:01:00 etc.etc..
In the stable version i have used here before all the sensors update at the same time a,b.and c at 19:00:00 and then all at 19:01:00 etc. etc..
What can i change or do that the sensors wil update all at the same time?
(sorry for my bad Englisch)