Question 1

What is EDID emulation and do I actually need it?

Accepted Answer

EDID is the handshake packet a monitor sends to the GPU describing its capabilities — resolution, refresh rate, color depth. Without EDID emulation, every time you switch computers, the GPU re-negotiates with both displays from scratch. Monitors flash black, resolution may drop to 1080p, windows scatter. With EDID emulation, the KVM holds the monitor's EDID signal constant regardless of which computer is active. Displays never know a switch happened. If you switch more than once or twice a day, EDID emulation isn't optional — it's the difference between a functional setup and a frustrating one.

Question 2

Can I use a Thunderbolt dock as a KVM switch between two computers?

Accepted Answer

No. Thunderbolt docks use PCIe tunneling, which only allows one host controller at a time. The dock negotiates a dedicated connection with whichever computer is plugged in — it can't be shared between two machines simultaneously, and routing two computers through one TB dock via a KVM switch breaks the PCIe link. Each computer needs its own dock, or you run the computers directly into the KVM without docks. If your goal is to share a Thunderbolt dock, that problem needs a different solution. For setups where both computers connect over USB-C, the AV Access iDock X10 functions as a KVM-dock hybrid — one device that switches both display and peripheral routing between two host machines.

Question 3

Why do my windows rearrange every time I switch computers?

Accepted Answer

The KVM doesn't have EDID emulation, or the EDID emulation is failing on one of the two output ports. When a monitor loses signal — even briefly — the GPU treats it as a monitor disconnect event. Windows responds by collapsing all open windows onto the remaining display. On Windows, FancyZones from Microsoft PowerToys restores your window layout automatically after every switch once configured. On macOS, Stay does the same. Both are free and fix the symptom immediately. The underlying cause is the KVM. If window scatter is disrupting your workflow across five or more switches a day, upgrading to a switch with full EDID emulation — TESmart or Level1Techs — is the permanent fix. For a comparison of which models handle EDID correctly, see the comparison table above.

Question 4

Does the Level1Techs KVM support hotkey switching?

Accepted Answer

Yes. Level1Techs supports hotkey switching via dedicated USB HID passthrough ports — there's a specific set of USB ports on the switch assigned to keyboard input for the purpose of hotkey detection. The hotkey sequence is configurable. What Level1Techs uses for display management is Smart HPD Suppression with transparent EDID pass-through, not active EDID spoofing. The distinction matters because active EDID spoofing breaks G-Sync, FreeSync, and VRR — Level1Techs preserves them by passing the real monitor EDID through rather than substituting a stored copy.

Question 5

What's the difference between simultaneous and independent monitor switching?

Accepted Answer

Simultaneous switching is the standard: both monitors switch to the other computer at the same time. Independent switching — available on the TESmart Dual Monitor KVM via Display Mode 2 — lets each monitor show a different computer simultaneously. Monitor 1 runs Computer A, Monitor 2 runs Computer B, and you move keyboard and mouse focus between them without either display changing. It's the closest thing to a software KVM experience in hardware. Most KVM switches only offer simultaneous switching — check the spec sheet before assuming independent mode is available.

Question 6

Can a dual monitor KVM work with a MacBook Air M3?

Accepted Answer

Yes, with one condition. Base M3 MacBook Air and MacBook Pro support two external displays, but only in clamshell mode — lid closed — and only on macOS Sonoma 14.3 or later. With the lid open, base M3 behaves like M1 and M2: one external display only. Base M4 MacBook Air removed the clamshell requirement entirely — two external displays work with the lid open or closed. M1 Pro, M2 Pro, M3 Pro, and all Max-chip variants support two external displays in all configurations. If you're building a two-monitor KVM setup around a Mac, confirming the chip generation first is worth doing before buying anything. For a full breakdown of Mac and docking station compatibility by chip generation, see the MacBook docking station guide.

Question 7

Do both computers need their own docking station?

Accepted Answer

Not necessarily. If your computers connect directly to the KVM via HDMI or DisplayPort — no dock in the chain — both video signals feed directly through the switch. Add USB-A cables for keyboard and mouse, and the KVM handles everything. Where docks become relevant is laptops that only have USB-C ports and need adapters for video output. In that case, the AV Access iDock X10 replaces the dock entirely — USB-C in, dual video out, and KVM switching built in. For setups with a Thunderbolt laptop as one of the two computers, each machine needs its own dock connected before the KVM, not after it. If you're choosing between a KVM switch and a docking station, the USB-C docking station guide covers when a dock is the better choice.

Question 8

Will a dual monitor KVM work with one HDMI monitor and one DisplayPort monitor?

Accepted Answer

It depends on the KVM. Most dual-monitor switches output both monitors over the same connector type — all HDMI or all DisplayPort. If your monitors are mixed, you'll need either a KVM with mixed outputs or an active adapter on one monitor.

The TESmart Dual Monitor KVM outputs both monitors via HDMI — it doesn't natively solve a mixed DP+HDMI setup. For mixed monitors, you'd need an active DP-to-HDMI adapter on the DisplayPort monitor's cable. If you go that route, use an active adapter rated for DP 1.4 bandwidth — passive adapters typically output HDMI 1.4 or 2.0, which caps 4K HDR and limits high-refresh rates at 4K. The Level1Techs KVM, by contrast, has two DisplayPort outputs — if your HDMI monitor has a DP input (most do), a DP cable from the KVM solves the mismatch entirely without an adapter.

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