Default M4R bitrate is 192 kbps (transparent for music). Override to 320 kbps (audiophile), 128 kbps (typical podcast), or 96 kbps (voice / smallest file). The choice trades file size against audible fidelity and is exposed in the advanced options before conversion.
װעט איך פֿאַרלירן די אוודיאָ קװאַליטעט װען איך װײַז פֿון MP4 צו M4R?
Silent gaps almost always mean the MP4 file had a multi-track audio layout (commentary, alternate languages, surround backchannels) and we picked the wrong stream. Use the advanced "audio stream" option to explicitly pick stream 0, 1, etc., or re-mux all streams to a multi-track M4R container if M4R supports it.