BTHome: Shelly BLU RC Button 4 — only button_1 event entity is created; presses of buttons 2-4 never surface

[LoneWolf345]

The problem

The Shelly BLU RC Button 4 (4-button BLE remote, BTHome BLE v2) only ever surfaces one button event channel in Home Assistant. event.<device>_button_1 is created and receives events reliably, but pressing physical buttons 2, 3, or 4 never creates button_2/button_3/button_4 event entities and produces no events at all — not on first press, not ever.

Verified on the device side that this is not a device/firmware problem:

• In the Shelly app, each of the four buttons appears as its own entity, and each one's "last report" timestamp updates correctly when that specific physical button is pressed — so the device transmits distinguishable per-button events.
• Device firmware is current (checked via the Shelly app, 2026-08).

Verified on the transport side:

• All Shelly Bluetooth proxies relaying for this install (Shelly BLU Gateway + 6× Gen3/Gen4 Shelly devices) were explicitly set to passive scanner mode (per the resolution pattern in BTHome Support for Shelly BLU Wall Switch 4 #127336). After that change, button_1 events flow reliably — buttons 2-4 remain completely absent.
• The related fix for the 4-button BLU Wall Switch 4 (working since 2024.12 per BTHome Support for Shelly BLU Wall Switch 4 #127336) does not appear to cover this device: same 4-button product family, but the RC Button 4's payload seemingly loses the button index in BTHome parsing.

Result: the integration treats a 4-button remote as a 1-button device. Press types (press / double_press / triple_press / long_press / hold_press) ARE correctly distinguished on the button_1 channel, so the payload parsing works except for button attribution.

What version of Home Assistant Core has the issue?

core-2026.8.1

What was the last working version of Home Assistant Core?

No response (never observed working for buttons 2-4)

What type of installation are you running?

Home Assistant OS

Integration causing the issue

BTHome

Additional information

• Device: Shelly BLU RC Button 4, BLE MAC 7C:C6:B6:9F:58:49, advertises as "Shelly BLU RC Button 4 5849", registered by BTHome as "BTHome sensor / BTHome BLE v2"
• Entities created: event.shelly_blu_rc_button_4_5849_button_1, plus battery / packet id / signal strength sensors. No button_2/3/4 event entities exist even after many presses of each physical button.
• Reception path: Shelly BLU Gateway + multiple Shelly Gen3/Gen4 BT proxies, all in passive scanner mode.
• Possibly related: BTHome Support for Shelly BLU Wall Switch 4 #127336 (BLU Wall Switch 4, resolved since 2024.12), bthome misses lots of Shelly BLU button presses with the latest version 2.12.1 #96605 (missed BLU button presses).
• The diagnostics endpoint for the BTHome config entry returns an empty response on this install; happy to capture debug logs of the raw advertisements (bthome / bthome_ble debug logging) on request.