I’m having a persistent hardware issue with my PiKVM V4 Mini.
The device experiences brief but frequent interruptions, roughly once a minute or more often. During each event, the HDMI video feed blanks and returns on its own (typically 1 to 10 seconds later). During the same window, keyboard input to the target host stops being delivered, and even a brand new SSH connection to the PiKVM itself will hang until the event clears. Existing SSH sessions remain open but are unresponsive during the event.
Here’s what I tried:
- Confirmed clean power delivery: vcgencmd get_throttled returns 0x0, vcgencmd measure_temp reads a normal 50.6°C, vcgencmd measure_volts reads a normal 0.87V core voltage.
- Tested with two different power supplies (original power pack and a Dell 65W adapter), no change in symptoms.
- Checked SD card health: no I/O errors in dmesg, no filesystem corruption in journalctl, card mounts cleanly.
- Disabled onboard WiFi (dtoverlay=disable-wifi), no change.
- Disabled CPU C-states in host BIOS, no change (this was a host-side test, since the freeze also affects host input delivery).
- Checked /proc/interrupts before and after an event: no IRQ storm on any peripheral.
- Watched dmesg -w and journalctl -u kvmd -f live through multiple events: no output logged during or immediately after a freeze.
- Reviewed the firmware log via vclog --msg: no errors correlating to freeze timestamps beyond routine firmware messages.
- Disconnected the ATX/RJ-45 cable to rule out electrical interference from that connection, no change.
- Fully reflashed the SD card with a clean, current stock image from files.pikvm.org (v4mini-hdmi-rpi4-aarch64-latest.img.xz, linux-firmware-pikvm 20251021-2), with no custom configuration applied. The issue is still present on the fresh install.
The problem persists identically across two independent OS installs, with power, thermal, SD card, WiFi, and known software/firmware issues all ruled out, and with nothing logged at the OS or firmware level during the freeze. Could this be a hardware fault on the unit rather than a configuration or software problem?
Can you tell me what else to try?
Thanks!