From now after trying with Steam Link for Android (also not working):
streaming_log.txt

I think I had some outdated TXT. Here from today's try, after changing into Beta in the SteamLink Hardware and trying to play wired (into the SL):
streaming_log.txt
steamlink_debug.txt

No problem under Windows with a laptop. So it is deffinetly a Problem with the Host.

Host system information

• Steam client version: 1541819448 (Nov 10 2018)
• Distribution: Ubuntu 18.04.1
• Opted into Steam client beta?: No
• Have you checked for system updates?: Yes

Steam Link system information

• Steam Link version: 1541819448 (Nov 10 2018)
• Opted into beta compilation?: No
• Have you checked for system updates?: Yes

Issue description

Gamepad (Logitech Wireless Gamepad F710) works flawlessly on Steam Link system and, when streaming, on Big Picture Mode. Gamepad is not recognized by any game. However, if Logitech (home) button is pressed, then the Big Picture Mode layer appears and, as said, gamepad inputs are followed.

In summary, gamepad works in-menu but not in-game.

Steps for reproducing this issue:

1. Start the Steam client on the host computer.
2. Plug the usb receiver into Steam Link and switch it on.
3. Use the gamepad on the Steam Link system to start the host's streaming.
4. Navigate through Big Picture Mode using the gamepad to start any game.
5. The game fails to respond to the gamepad inputs.

Workaround

After step 3 above, unplug the usb receiver from the Steam Link and plug it into the host computer. (It defies the purpose of the Steam Link if the device and the computer are in separate rooms.)

Extras

I have tried to "switch to modern Xbox controller driver" from Steam Link system menu with no success.

This is a well known problem since more than a year ago as stated in Steam Community forums. I am quite displeased to see that. We bought a device whose purpose can't be achieved and it has been known for more than a year. Deceiving.

Attachments

steamlink_debug.txt not found
streaming_log.txt

@alfonsoler since the problem happens with several gamepad, I suggest you change the issue tittle to something like "gamepad works in-menu but not in-game" or "gamepad not working in-game, only in-menu".

@kisak-valve Perhaps add a "Steam Link" label to the issue? It is more suggestive than "streaming".

@vitaminace33 it seems that i can't change it, but would be a good idea if a moderator can do it.

The problem is a Host problem, so I do not know if the SteamLink label would help. Here the answer of Steams Support:

Hello again,

Thanks for clarifying that for me. Now, i understand that this issue is only prevalent when using the Steam Link, but because the issue is specific on connection to the Linux Host, rather then on the Steam Link Menus, your best bet is to share your experience on the GitHub.

I apologize for the inconvenience, and I am sorry that I do not have a more immediate solution for you.

Thanks for using Steam,
Cole

Out of curiosity, I have tried a keyboard and mouse (Logitech Wireless). They both worked perfectly, so it seems it is restricted to gamepads. Since the Logitech Wiresless Gamepad F710 is an Xbox-like controller, I wonder if this happens also with PlayStation controllers. It would be of interest if someone could test this or even other controllers.

@alfonsoler, it is not clear to me what do you mean by "host". Just to be specific: Since this happens only on Steam Linux + Steam Link + Gamepads and since the gamepad works on the Big Picture Mode menus, which are part of the Steam Client, I guess the problem is that the Steam Client fails to transmit the gamepad inputs to the game.

Also, you are on Gentoo and I am on Ubuntu, so it doesn't seem to be distro specific.

That said, little off-topic, are you Spanish?

Gentoo? No no, Ubuntu 18.10 (I thought it was maybe a problem with the upgrade but I see you have 18.04 so...).
And were the mouse and keyboard connected to the Link?
Y sí, se me ha visto el plumero ;)

Gentoo? No no, Ubuntu 18.10 (I thought it was maybe a problem with the upgrade but I see you have 18.04 so...).

True, not Gentoo. My bad, I confused it with another thread. I will try on Arch Linux.

And were the mouse and keyboard connected to the Link?

Yes.

Y sí, se me ha visto el plumero ;)

Pozí, el apellido te ha delatao.

From today's try with Amazon FireStick TV 4k (also not working with the Gamepad connected to the Stick via bluetooth. Only working if connected directly to the PC):
streaming_log.txt

Solution: sudo apt-get install steam-devices && reboot

That worked right now with the Fire Stick! Thank you. I will test it further later on.

;-) GL

Just one problem: RT and LT are inverted (?)

For me, all ok. Check it on the Link system, before connecting to the client (i.e. streaming). You can reset the button biding map and check if the default one is correct. If you then still have problems, it must be some controller configuration in the client or the game. Remember to activate "Xbox support" to have per-game settings.

Happy to hear that it works.

@alfonsoler, mark the thread as "solved".