TESmart HDMI KVM Switch 4 Port 4K@60Hz, KVM Switch 1 Monitor 4 Computers EDID Emulators, USB 2.0, L/R Audio, Hotkey Switch, Button Switch with Remote Controller and All Cables

This KVM seems like a good value for money. Here are some details I thought I’d share since I wasn’t sure about them the moment I bought it and not many people mention them:- Supports EDID emulation. That is, when you’re switched to one device the rest of the devices think the display is still attached to them, so they behave nicely, instead of shifting windows around as if you unplugged the external monitor.- HDCP is supported according to the nVidia Control Panel.- USB is 2.0. That’s okay. I don’t think there are many uses for USB 3.0 on a KVM. I don’t think storage devices should be used on a KVM, and you don’t need to switch a network adapter between computers, you just connect all the computers to the network with a normal ethernet switch.- The included cables have the HDMI and USB parts stuck together. That is nice because it keeps everything tidy. You can also separate the cables as much as you need. Now I want to buy the optional extra 2 cables.- LEDs are blue. Very bright, you know the type...- Runs very cool. Uses less than 5W.- The device is a little ugly but hey, there’s a desktop version also, a little prettier (comes in red, black or blue). I’m mounting it under the desk so I needed this version with the screw holes.- The “Online” LEDs detect when the USB cable from the computer to the KVM is connected, not the display cable.- Power brick doesn’t take additional space if your power strip is aligned the traditional way (like this = = = = = = ), big plus.- Remote doesn’t have a lot of range, but you never have to press a button twice. The thing I dislike about remotes powered by coin cells is that you seem to need to press the buttons multiple times for them to do something. This one has nicer quality buttons so whenever the remote is in range (is not as powerful as a TV’s) it’s going to work reliably. If the KVM is bolted under your desk, you’re going to have to point the remote under your desk.- If you ever run into issues with black/green screens after switching back and forth to one device, try using a different output or a different converter combination (see details below).- I have no idea what the M and P buttons do on the remote.—- USB COMPATIBILITY —-- Tested with Logitech Unifying Receiver that is connected wirelessly to a Logitech K850 keyboard and a Logitech M720 mouse- Hot keys work with this setup (you can press Scroll Lock twice then press PgUp/PgDown or 1, 2, 3, or 4 to select inputs).- Hot keys work only on the top row of numbers, not with the number pad. I think this applies to all keyboards.- The Logitech software (Logitech Options) will not detect your mouse and keyboard as Logitech if you are plugged into the KVM's mouse and keyboard USB ports. This is because the KVM connects directly to them and emulates a virtual mouse and keyboard and presents that to the computer. If you want Logitech Options or similar software to work, you have to plug the mouse into the third USB port, the one for devices. Hot keys don't work on that third port, though.—- VIDEO COMPATIBILITY —-- I found a compatibility issue using a Dell WD19 docking station and Apple devices. Both of these have a workaround, please read below.- 2020 M1 MacBook Air -> Dell WD19 docking station HDMI output -> TE Smart 4x1 KVM -> LG Ultrafine 25UM58 (resolution 2560x1080) —->>> NOT WORKING, display goes black or dark green after switching from this source to other source and back to this source. You have to disconnect and reconnect again.- 2020 iPad Pro 12.9” -> Dell WD19 docking station HDMI output -> TE Smart 4x1 KVM -> LG Ultrafine 25UM58 (resolution 2560x1080) —->>> NOT WORKING, display goes black or dark green after switching from this source to other source and back to this source. You have to disconnect and reconnect again.-This incompatibility CAN BE SOLVED if you use the Dell WD19’s other outputs. I tested this chain and it works:- 2020 iPad Pro 12.9” -> Dell WD19 docking station USB-C DP output -> Apple USB-C Digital AV Multiport Adapter ->TE Smart 4x1 KVM -> LG Ultrafine 25UM58 —->>> WORKS- It should work on the M1 MacBook also but I didn’t test; the computer was borrowed.- Other adapters could work too. I think that the WD19 has an internal HDMI adapter that doesn’t like the KVM for some reason. There seems to be a timing/sync issue because the display shows multi-color noise or static then goes black. Anyway, this setup is for one display output so you don’t lose anything by using an adapter on the other port.I tested these and they worked and also worked after switching back and forth:- Dell Latitude 5300 -> Dell WD19 docking station HDMI output -> TE Smart 4x1 KVM -> LG Ultrafine 25UM58- PC with RTX 2060 native HDMI output -> TE Smart 4x1KVM -> LG Ultrafine 25UM58- PC with CableCreations DisplayLink USB to HDMI adapter -> TE Smart 4x1KVM -> LG Ultrafine 25UM58- 2020 M1 MacBook Air -> Apple USB-C Digital AV Multiport Adapter -> TE Smart 4x1KVM -> LG Ultrafine 25UM58- 2020 iPad Pro 12.9” -> Apple USB-C Digital AV Multiport Adapter ->TE Smart 4x1 KVM -> LG Ultrafine 25UM58- 2014 MacBook Air -> generic Mini DisplayPort to HDMI adapter -> TE Smart 4x1 KVM -> LG Ultrafine 25UM58- 2020 M1 Mac Mini via native HDMI -> TE Smart 4x1 KVM -> LG Ultrafine 25UM58--- AUDIO ---The 3.5mm audio output works this way: it intercepts the signal from the selected HDMI input and it outputs the oudio for that selected input. I'm not sure if the monitor also receives the signal. The audio quality is better than my monitor and better than my Raspberry Pi 3B. The output doesn't have any hiss or noise, which is great. I don't normally expect these types of products to have good sound.Note that Apple devices can't adjust HDMI volume for some reason. It's Apple's fault though. Very frustrating.I will be adding more devices as I test them (Raspberry Pi 3B, Raspberry Pi 1B, generic DisplayPort adapter on the WD19 dock instead of Apple USB C adapter, etc.). I can’t test HDR support.To be honest I’m glad I found a workaround for the Apple + WD19 incompatibility, because this KVM is very very nice and that would have been a dealbreaker. I don’t think it’s the KVM’s fault given it worked with everything else so I’m giving it 5 stars.

Update after 3 months of use:The issue with the keyboard skipping characters never improved and was becoming more and more of a problem since I use this thing for work, and am on a computer a large part of the day. Transposed characters (e..g "dgo" when I meant to type "dog") happened too often to be operator error.I'd been debating moving it back to my pre-TESMart configuration (mechanical keyboard connected to a powered USB hub, and that USB hub connected to the KVM) for quite some time, but I didn't want to give up the keyboard switching feature. I put up with it for far too long.Well, keyboard switching gave up the ghost yesterday. No clue why - I had not reconfigured anything. Just ctrl-ctrl-1 (etc.) no longer did anything. Turning it off and on did not fix things. at this point, there was absolutely no reason to try to put up with the other problems any more.I moved the keyboard to the external hub, plugged that into the KVM, and suddenly typing has become massively more accurate. I've lost the ability to switch via the keyboard, but the remote works (for now.....). I'll have to Velcro it to the keyboard so it's always handy.All in all, this has been a huge waste of money. I should have gotten a less expensive KVM that did NOT claim to be compatible with mechanical keyboards, and just included a remote.Update after a week of use:The keyboard switching works just fine - ctrl-ctrl-1 / 2 / 3 / 4 switches computers quite nicely. The remote does as well.But I'm downgrading to 2 stars, because I'm having MAJOR problems with keystrokes not registering. For example "Mary Had A Little Lamb" will show up as "MaryHa A Little Lam". It also seems like more swapped letters are happening, e.g. I type "Lamb" and see "Labm". I don't know if that's an artifact of the keyboard's connection, or if it's operator error - I certainly can make such mistakes, so I don't insist that the switch is the problem.I did make sure things were plugged in correctly and securely, which has not solved the problem. My next step will be to try plugging the keyboard into a powered external USB hub, then feed that to the KVM - precisely what I did before buying the TesMart. That would also render the hotkey switching useless - and that was the main reason I bought this model! Oh well, at least the remote should still work.********************************************************************(Since there are several models shown: I have the 4 port, 1 monitor, USB 3.0 model)I was using another brand of KVM, but when I switched to a Corsair K70 mechanical keyboard, I found that I'd lost the ability to switch computers using keyboard hotkeys. In fact, to get it to work at all, I had to plug both cables into a powered USB hub, and feed THAT to the device - otherwise, it either didn't work at all or the computer showed garbage when I tried typing. The other device didn't have a remote, either, so when I wanted to switch, I had to lean up to where the KVM was mounted (not within easy reach) to make the switch. TESmart claimed that theirs works with mechanical keyboards, so I gave it a try.Observations after having JUST set it up:- Keyboard switching DOES work. That was the sole reason I went for this new KVM switch.- Mouse gesture switching does not (may be operator error, but I never used that before, so I'm not too worried). I'll likely play with it some more - may have disabled when I meant to enable, or something.- The included cables really are needed: the computer-to-device plug is a different one than my older device. Both are USB-B, but apparently the 3.0 version of USB-B is actually configured differently. So if, like us, you've got a pile of USB-B cables lying around, they won't help you here.- The included cables are QUITE stiff. My setup involves wire shelving, with a shallow shelf for the KVM; the cable stiffness meant that attaching them all, and shoving the whole mess back onto the shelf, was more of a challenge than it needed to be. At some point I may purchase separate USB-B 3.0 cables to see if that's easier to manage, though I don't anticipate needing to move things around all that often. I also worry a bit about the stiff cables putting stress on the computer ports they are attached to.- The product description claims there is no delay when switching. That is simply not true - I counted, and it's roughly 3 seconds before the new computer's screen shows. Not a big deal for my purposes, but if you need a truly instantaneous switch, this may not be the right device for you.- Pass-through functionality is not perfect. My keyboard has a USB port on it - which I frequently use to plug in my USB headset. This simply did not work: the computer did not detect the headset. Weirdly, it worked just fine when I tried plugging a spare mouse into the keyboard. I don't know if this has anything at all to do with the switch's audio functionality (which I have not explored, as I don't need it). The headset works fine when plugged into the port on the front of the switch, so I'll likely just do that. Still, it's annoying.I have both keyboard cables plugged into the kb/mouse USB plugs, and the mouse plugged into the other plug on the back of the device. I may try alternate configurations (e.g. moving one of the keyboard plugs to the alternate) to see if that solves the passthrough issue. If so, I'll update this review.