No. According to download statistics, the official firmware is quite enough for most users. No. Only to explicitly listed.

Add-on v.1.31 is compatible with the firmware version 1.09.350.

The change "A different approach to control brightness at low levels" in my add-on was an attempt to address this problem, and it makes no significant difference. Just because the backlight of this display at its absolutely minimum level is too bright.

Add-on v.1.30 is compatible with the firmware version 1.08.338.

The newer firmware includes drivers for both screen versions, and also for both touchscreen versions (they are different as well). The new drivers start first. Unlike full Android, pure Mango can't handle touchscreen driver change "on the fly", so I had to implement the boot process to wait for...

If you believe your problem is related to the add-on, please uninstall it by flashing the official firmware.

No idea! 1200+ SD-card version downloads of the previous version, 23 downloads on this version, and only one such complain. If you have an access to a Windows PC, I'd suggest to try AndroidTools method.

Right: first flash the official update, then apply the new add-on. It's up to you which installation version of the add-on to use: using AndroidTool or bootable SD-card.

Add-on v.1.29 is compatible with firmware 1.07.250. Mango OS has been updated from DX220 firmware 1.19.324. So far I performed only a quick test, hoping that it will work not worse than the previous build.

Add-on v.1.28 is compatible with the firmware 1.19.324.

I use a similar charger, 65W from Baseus, along with 15V Type-C to barrel decoy cable (mentioned in this thread many times). Both purchased off AliExpress a long ago.

I don't understand you. Please read the description of the USB Audio application with attention, and if the problem still persists, either disable USB Audio support in the app (better) or PM me if you really need this feature (explain why).

The beauty of a DAP with full Android is the ability to fully utilize its hardware capabilities with 3rd party apps. From my experience, Android is rock stable in DX160. I use it with Neutron and face no problems.

This may be caused by faulty Power button, because this kind of shutdown is implemented in hardware. If course it will turn off. But if your device has a problem with Power button, it would be hard to turn it on again. Just try if the usual method does not work.

The device must be disconnected from a power supply when you do it. Another reason can be that you count 10 seconds too quickly. Then try 15 seconds.

In the PM you provided more details: "Dx220 booting up in recovery mode and being detected with "Found one ABD device"". Most probably, it means that you don't follow the instruction: either you have no Rockchip drivers installed, or you push Power button. Please ensure you have the drivers...

Add-on v.1.27 is compatible with the firmware 1.19.294.

Add-on v.1.25 is compatible with firmware 1.02.143.

OTA update to 1.18.284 is available now.

Add-on v.1.26 is compatible with firmware 1.18.284.

Such batteries with advertised capacity far beyond possibilities usually have far less capacity that the original battery. You'd better buy directly from iBasso or its dealer.

This usually happens when DX160 is turned on holding Play button. Try to disconnect DX160, force turn it off (press and hold Power for >10 seconds, then release), and try to turn it on again. Note, that you always can recover DX160 from bad flashing by loading full firmware image from the first...

Are you sure you listened to the same track with only different encodings and not different mastering versions? The link I provided contains tracks different only by encodings. They sell MQA. What do you expect from them?

You may try to perform factory reset, then install Tidal and UAPP and check, without changing anything in USB Audio application.

Don't touch it again until you have fully understand how it works.