DisplayLink Forum - strange keyboard-lag of HP PR3005 in combination with Kensington wired keyboard

Hi all,

Hope someone is able to help solve the following problem. Trying extensive googling but seems we're the first / only one experiencing it.

My organisation installed app. 900 port replicators (HP 3005PR) last july with the following peripherals:

Kensington Advance Fit Fullsize slim keyboards (wired)
generic dell mouse (wired)
Dell 24" monitor (p2414H).
USB 3 connection cable

Network is wireless so not connected to the replicator.

During initial deployment we were only able to install 50% of the workspaces with the Kensington keyboards due to a logistics failure, the rest of the keyboards were installed early october. From july till october the other half of the workspaces were equipped with old generic Dell keyboards.

immediately after the second half of the workspaces was equipped with the new Kensington keyboards reports started flowing in that users were experiencing strange random lag: random letters and numbers got 'stuck' (printing 10-30 times the same letter or number, sometimes nothing happened when pressing a key repeatedly) and the poor soul that happened to use the backspace key sometimes saw several words or even rows of text disappear. Sometimes it happened multiple times within seconds, sometimes once every minute and sometimes it just stopped happening for one hour or longer.

So far we've tried the following:

1. restart laptop (no fix)
2. powercycle the replicator (partial fix for some, not for majority)
3. change usb port (partial fix for some, not for majority, both from usb3-usb3 and from usb3 to usb2 port)
4. reinstall drivers (no fix)
5. switch out replicators (no fix, solved it for maybe one / two workspaces)

Initially it seemed that the problems were directly related to us switching the keyboards (old Dell -> new Kensington), but we're now also seeing affected workspaces which no other keyboard has been connected to than the Kensington one (although -in at least one instance- it may be that in those situations a broken Kensington keyboard was replaced by a new one)

Everyone is using pre-installed, managed Windows 7 laptops using the same displaylink software driver (I believe it's 7.6m2 or 7.7m0). It's also happening on (self-support) laptops running the latest (7.7m0) version with all drivers up to date. Kensington does not provide any drivers for the keyboard. Connecting the keyboard directly to the laptop solves the problem

We're pretty much at a loss here as we can't reliably reproduce it and it happens randomly. If anyone has any tips on how to either troubleshoot it further or solve this I'd be very grateful. Maybe we should also contact HP but I'd rather try here first :)

If diagnostics are needed I'm more than willing to provide them.

Kind regards,
Pascal