Hello everyone! I solved a problem with low mic level in MIUI v1.9.16 by replacing these three files: /system/lib/libaudio.so /system/etc/firmware/default.acdb /system/etc/firmware/htcleo.acdb I took these files from Hyperdroid GBX v12.0 ROM(there is no problem with low mic), then I modified the original MIUI ROM .zip archive by these files and installed it into my HTC EU HD2. And fortunately it works as I want! Possibly it will be helpful for somebody who has the same trouble with low mic level. Best regards, Ivan.