Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

tdewolff · 2026-08-12 20:49:12

I have a Dell keyboard and mouse connected through a USB dongle that has a Bluetooth connection with the devices. The mouse is fine, but the keyboard often misses keystrokes when I type fast (happens often!) or occasionally repeats a key a couple of times.

I have added the following udev rules:

# /etc/udev/rules.d/50-usb_power_save.rules
ACTION=="add", SUBSYSTEM=="usb", TEST=="power/control", ATTR{idVendor}=="413c", ATTR{idProduct}=="850    5", ATTR{power/control}="on"
ACTION=="add", SUBSYSTEM=="usb", TEST=="power/autosuspend", ATTR{idVendor}=="413c", ATTR{idProduct}==    "8505", ATTR{power/autosuspend}="-1"

# /etc/tlp.d/01-usb.conf
USB_AUTOSUSPEND=0

I don't think the Bluetooth settings need to be tweaked (its service is disabled anyway) since this is a USB connection.

Not sure what else to try? Any suggestions would be helpful. otherwise if it's a hardware issue I'll just have to buy a new keyboard/mouse set.

mmy8x · 2026-08-13 04:03:47

It could be something Bluetooth-related, I don't know.

Or it may be a certain lame USB issue; does it help to move the dongle to a different port, perhaps on a different bus (see lsusb)?

seth · 2026-08-13 06:19:15

Those dongles typically use BT-adjacent but proprietary protocols but are not general purpose bluetooth controllers.

Can you connect the keyboard using a usb cable as well?
(could be the actual keyboard electronics, I assume it's a rubber-dome?)

Do you run a wifi? On 2.4GHz? or 5GHz?
Different port is certainly a good idea to test, not so much because of its performance (keyboard/mouse should™ be happy on 1.1…) but because of its physical relation to antennas and other interfering/shielding elements of the hardware.

mmy8x · 2026-08-13 06:29:42

If this isn't actual Bluetooth, but something that looks like a USB keyboard to the host, then even more likely to be the USB bug. Basically, usbhid driver's recovery from USB bit errors isn't very sophisticated, it may drop the corrupted report or even the next one. If you lose a single mouse movement report, you won't notice. If you lose a key press or release report, it looks exactly as described by OP.

So meh, until somebody fixes that, try other USB ports, cables, etc.

tdewolff · 2026-08-13 20:16:22

Thank you mmy8x and Seth for the replies. Switching to another USB port has helped. I have a Thinkpad T460 and all three USB ports are 3.0, but I've changed from the left-farthest to the right, it is somewhat closer and probably closer to the emitter in the keyboard. It is also the always-on port (which helps?).

I do have a WiFi connection at 5 GHz (it also supports 2.4 GHz, but I believe that would interfere?). The keyboard doesn't have a cable, it pretty much the older variant of this one: https://www.dell.com/en-us/shop/dell-pr … ccessories

Last edited by tdewolff (2026-08-13 20:16:48)

mmy8x · 2026-08-14 04:22:52

It's a matter of USB link quality: for whatever random reasons, this device must be suffering occasional USB packet loss while working in the "left-farthest" port, which usbhid doesn't handle very well, i.e. it entirely misses the fact that some keys have been pressed or released. This is known to particularly affect USB 3.0 hosts (xHCI) and sometimes also low/full-speed devices behind hubs even on EHCI. (Actually, ancient USB 1.0/1.1 hubs are safe, but who even has them anymore?)

Arch Linux

#1 2026-08-12 20:49:12

Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

#2 2026-08-13 04:03:47

Re: Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

#3 2026-08-13 06:19:15

Re: Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

#4 2026-08-13 06:29:42

Re: Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

#5 2026-08-13 20:16:22

Re: Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

#6 2026-08-14 04:22:52

Re: Keystrokes missing or repeated on Dell Universal Receptor [USB+BT]

Board footer