@tapaniraja What level of control are you looking for, exactly? Depending on the version, Android has a built-in AudioFX app with an equalizer and a few other controls.
And we use this (proprietary) app on the ones that don't (use a firewall or adblocker to block internet access if you use the free version): https://play.google.com/store/apps/details?id=com.devdnua.equalizer
If you're looking for something that's as powerful as PulseEffects for Linux, for example, we sadly don't know of anything close to that level.
@KitsuneAlicia Simply more precise control of the volume and basic EQ. The most annoying thing currently is that the steps the volume increase and decrease is huge, especially with external speaker. Can't get the perfect volume.
@tapaniraja Ah. There's ways to adjust the number of volume steps for the bbuilt-in volume controls, but they require using Xposed, and installing that isn't for novice users, unfortunately.
If you're up for it, though, you can look up an Xposed module called GravityBox.
If not, you might be able to get a similar effect by using lower settings on an equalizer like the apps I mentioned up above.
@tapaniraja Oh, another thing is to check Android's Settings. Specifically, go to Developer Options and look for an option called "Bluetooth Absolute Volume" and disable it if it exists.
(If you don't see Developer Options, you'll need to go to About Phone and tap the Build Number field 7 times to unlock it.)
@Vael It says it's not recommended because it might interfere with existing features within custom ROMs like LineageOS or otherwise not work due to different implementations of various features, but most things in it should work.
We've used it with a XenonHD ROM (offshoot of SlimROM) on our old phones and I think the only issue was that the "Hide 'no SIM card' icon" setting from the status bar section didn't work.
@tapaniraja I use Precise Volume. it has basic EQ and allows volume tweaks one percent at a time, where on my phone it jumps by quite large values when I use the buttons.
@jlbee Will look into this! I'm encountering the exact same issue. Super annoying especially with an external speaker.
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