After an upgrade of the DropdownListModule from 2.x to the latest stable version the reset() method only resets the value field and not the text field:
Example: https://stackblitz.com/edit/angular-f7dpzf-wzj24n
Same undesired behavior can be observed when the data items are objects with and without valuePrimitive set.
Note: reported in a support thread - Ticket ID: 1341261
The fix is available in the dev channel of the @progress/kendo-angular-dropdowns package v3.2.1-dev.201810300907.
Shipped in @progress/kendo-angular-dropdowns v3.3.0.
Problem is still alive. After calling reset, item selection stayed at the same place.

@GenaANTG Thanks for your input!
I tried it out with both primitive and complex data, with and without a default item and I couldn't reproduce the issue. See this example for reference.
The unwanted behavior at your end could be caused by the package-lock.json file which could hold a reference to the old dropdowns package. Try deleting it and running the following afterwards:
npm install --save @progress/kendo-angular-dropdowns@latest
If I am missing something and the proposed solution doesn't solve the issue, please provide more details on how to reproduce it. A runnable StackBlitz example would be best.
@dimitar-pechev Thanks! Okay, i'll tried to delete package-lock.json and cache clean.
@dimitar-pechev looks like problem still alive, Dimitar, i found few bugs with combobox. In short time i'll made report and reproduction of them.