Hi @klikirill-at-yandex-ru, the voice indeed has changed. Some learners reported the new voice reminds them of Benedict Cumberbatch :) You can't change the voice back, but we'd be very interested to learn what you think the new voiceover is missing.
The reason we are switching to new voice engines is because using the new voices we can provide you more choices in the future. For example, the new voices can be male/female and have multiple speed options in the future. We are always trying to make the learning experience more pleasant but some changes are unavoidable to move forward.