How to disable charging connected USB device (S9)

[PSte]

Hi. when I connect USB flash drive to my Samsung S9, phone starts to charge this flash drive:

"Andriod system - USB charging connected device"

I am not able to turn this off in any way. This happens when I connect USB flash drive through USB adapter included in package or even USB C drive (dual USB A/C micro SD card reader). During the period it is connected the flash drive gets quite hot. I just don't understand why phone wants to charge a flash drive. Is there a way to turn it off? Thanks.

Model: SM-G960F

Android: 8.0.0

Samsung Experience: 9.0

[Woody]

Is there not an option in the pull-down notifications that you can change to transfer files only. (or something to that effect)

[PSte]

Well there are more options what to do...

When I tap the second one (charging) I have these options:

 When I select "Transfer files" the process of reconnection starts, or something like that and I get to the same state as before. So this doesn't help at all.

But I'd like to set default behavior for USB flash drive not to do this every time even if this works fine.

[Reginard]

Not sure if this will help but under Developer Options in Settings, there is an option for USB Configuration (it's quite a way down) this seems to set the default for how the USB port is used.  Mine is set to MTP and I don't have the problem you are experiencing.

[PSte]

I have the same setting, maybe different build...

[SnakeGold]

This is a bug since the galaxy s8 and samsung has not corrected it.

[ishmo65]

My phone's USB option is set to MTP but the phone notification says "USB charging connected device". Whether i leave it or change it to Transfer files from the notification, my USB flash drive is overheating .... so this is with the developer option for USB already set to MTP. After a while the device disconnects, probably because it's overheating.

[Misael71]

I have the same problem but different situation. I connect my Ps4 controller and it starts charging I did go on Developer options only transfering files but it still charges my controller and drains the battery 

[SnakeGold]

The problem still exists and they haven't done anything to address it.

[Lifeisfun]

Yes, still not fixed, very frustrating, same on Tab A 2017, that I like to connect to drone controller but it drains the controller at the same time.