Doorbel answering slow and stops frequently

The doorbell is unusable. If I answer it it takes more than 5 seconds before anything happens. If I want to talk the connection frequently drops, it is impossible to talk.
What can I do to fix this?

Did you contact customer service??

No, I thought this forum can be used for that. I will contact them through their site

your problem needs specific analysis

After fimware release of the doorbell 2.2.2.1 the problem has been solved! Using it now a couple of weeks had no problems anymore!