Does maybe the change of used stream changes your behaviour?

Section in sys file:

[android]
navigation_audio_stream=4
; 0-STREAM_VOICE_CALL, 1-STREAM_SYSTEM, 2-STREAM_RING, 3-STREAM_MUSIC, 4-STREAM_ALARM, 5-STREAM_NOTIFICATION; <<= explanation of values

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Or navigation_audio_stream=3, or...