I noticed that compared to the original cowon line-in recording level set to "10" I already get a lot more gain with Rockbox's max gain (12 dB).
Question: Is it possible to tweak some firmware parameters to increase the sensitivity even more to "mic-in" characteristics?
I'm using Soundman OMK ear mics + pre-amplifier which in fact do give me enough gain when recording in front of a stage at high signal levels. But I'm not very happy with low-level signals like recording birds in a forest for example.