Voice is recorded, music not

[frans.de.roy]

Hi, I'm using OBS to transfer MiniDV recordings with a Sony DCR-PC110E PAL camera to .MP4 files . I use a HP Windows 11 laptop and OBS 32.0.4. I use a Gembird video grabber and made the connection with both an S-Video cable and white/red RCA cables. I can grab video and audio, but for audio I ONLY receive voice and not music such as playing a keyboard etc. When somebody is playing the keyboard and talking as well, I get some some music, but when the person stops speaking the audio fully disappears???

Is MiniDV using different tracks for voice and other sound? All 6 tracks in the OBS audio mixer advanced properties are set to active, but are there other configuration actions I need to take? Can somebody please help??

Thanks in advance, Frans