Word stress lesson a bit frustrating – Babbel – Learn Russian Review

Some of the audio files are clearly stressing the first syllable when it says the last syllable (specifically “мука, духи, замок,” and “ресторан” sounds like the emphasis is in the middle). Is it a matter of elongating, or different kind of emphasis on these syllables? The distinction would be helpful.
Review by Al babes on Babbel – Learn Russian.