OnePlus 12 → 3 Bluetooth Headphones, Same Audio

The core constraint — why 3 is hard

Classic Bluetooth audio (the A2DP profile) is point-to-point: one source streams to one listener. Everything below is a way around that one-to-one wall. Phone makers added "share to a second device" tricks (Apple Audio Sharing, Samsung Dual Audio) — but those stop at two. There is no native "play to 3 headphones" toggle on any mainstream phone, OnePlus included. Getting to three always means a different transport: a broadcast standard (Auracast) or an external splitter/transmitter.

Your device — OnePlus 12

Bluetooth version: 5.4 — new enough to support LE Audio & Auracast broadcast (high confidence on hardware)
Chipset: Snapdragon 8 Gen 3 — its audio stack supports LE Audio
Headphone jack: None. USB-C only — so any wired option needs a USB-C → 3.5 mm adapter first
OS: OxygenOS (Android 14/15). Auracast UI ships with the OS — availability depends on your exact OxygenOS build (verify on device)
Native "Dual Audio"?: OnePlus has no reliable built-in 2-headphone sharing like Samsung's. Don't count on a stock toggle (verify)

The 3 ways to do it

① Auracast (Bluetooth LE Audio broadcast) Best for 3+ · if compatible

The proper modern answer. Your phone becomes a broadcaster and sprays one audio stream to an unlimited number of receivers — 3, 5, a whole room. No "primary/secondary" pairing limits.

The catch: it only works if all the pieces support it — your OnePlus 12's software and every one of the 3 headphones must be Auracast / LE Audio devices. Most headphones sold before ~2024 are not.

Pros

Unlimited headphones · best sync · no extra hardware · low battery drain

Cons

Phone OS must expose it · every headphone must be Auracast · still rolling out

To use it: check Settings for an "Auracast" / "Audio sharing" option (see checklist below), and buy/own 3 Auracast-rated headphones.

Hardware: ready. Software + headphone support: must verify — don't assume.

② USB-C Bluetooth transmitter (multi-link) Works with ANY headphones

A small dongle plugs into the OnePlus 12's USB-C port and re-broadcasts the audio to several ordinary Bluetooth headphones at once. The phone "sees" a wired audio device; the dongle does the Bluetooth. This is the most reliable path if your 3 headphones are regular (non-Auracast) Bluetooth.

Key when buying: most cheap transmitters only do 2 simultaneous ("dual link"). You must pick one that explicitly lists 3+ simultaneous connections — or an Auracast transmitter (which then needs Auracast headphones again).

Pros

Works with any Bluetooth headphones · no OS dependency · portable

Cons

Extra dongle to carry/charge · few support a true 3 · slight latency

Look for: "USB-C Bluetooth transmitter, 3 devices / multi-stream" (brands like Avantree, 1Mii, Creative). Verify the 3-connection spec before buying — the 2-device ones are far more common.

Reliability: high once you have a genuinely 3-capable unit.

③ Wired USB-C splitter Cheapest · never drops

Run the audio out as a wire and split it three ways. Because the OnePlus 12 has no 3.5 mm jack, the chain is: USB-C → 3.5 mm adapter (DAC) → 3-way headphone splitter → your 3 headphones (each used in wired mode via their 3.5 mm input).

Pros

~€10 total · zero latency · perfect sync · never disconnects

Cons

Everyone is tethered by cable · needs headphones with a 3.5 mm input · volume drops a bit across 3

Buy: 1× USB-C-to-3.5mm DAC adapter + 1× 3-way (1→3) 3.5mm splitter + 3.5mm cables for each headphone.

Works tonight: guaranteed if your headphones accept a 3.5mm cable.

Which one for you?

All 3 headphones are new / Auracast-capable → go ① Auracast (check your phone first).
Mixed or older Bluetooth headphones, want wireless → ② USB-C transmitter rated for 3.
Want it working today, cheaply, cables OK → ③ wired splitter.

Option ② up close — 5 current USB-C transmitters

Honest ceiling: every current transmitter is dual-link = 2 headphones max with ordinary Bluetooth. Only an Auracast transmitter feeds 3+, and then all headphones must themselves be Auracast.

#	Model	OnePlus 12 fit	At once	Any headphones?	~€
1	Twelve South AirFly USB-C	USB-C ✅ direct	2	✅ any BT	~55
2	Avantree C81	USB-C ✅ direct	2	✅ any (verify Android USB-audio)	~40
3	KOKKIA USB Splitter	USB-C ✅	2	✅ any BT	~60
4	1Mii B03Pro	3.5mm ⚠️ needs USB-C→jack DAC	2	✅ any BT (best range/quality)	~60
5	Avantree C82 Aura (Auracast)	USB-C ✅	3+ / ∞	❌ only Auracast	~60

Skipped the popular Creative BT-W5 — it's single-device fast-switching, not dual, so it can't do even 2 at once.

The Auracast headphone market (late 2025 → 2026)

If you take the Auracast route, this is the current landscape — confidence-tagged, because several models only gained Auracast through a firmware update (same model name can mean yes or no depending on its software).

#	Model	Type	Auracast	Conf.	~€
1	JBL Tour ONE M3	Over-ear	Native — first consumer over-ear w/ dual Classic+LE Audio	High	~300
2	Samsung Galaxy Buds3 Pro	Earbuds	Native — best inside Samsung ecosystem	High	~220
3	Samsung Galaxy Buds3	Earbuds	Native	High	~150
4	Technics EAH-AZ100	Earbuds (premium)	Added via firmware	High	~280
5	Sennheiser Momentum TW 4	Earbuds	Added via firmware 5.15.4 + app	High	~250
6	Google Pixel Buds Pro 2	Earbuds	LE Audio / Auracast	Med-High	~230
7	EarFun Air Pro 4+ 💰	Earbuds (budget champ)	Native — sub-€100, BT 6.0	High	~90
8	Avantree Aura Focus	Earbuds	Dedicated Auracast budget pair	Med	~60
9	JBL Tour Pro 3 / Live Buds 3	Earbuds	JBL 2024+ LE Audio line — verify firmware	Med	~200
10	Bose QuietComfort Ultra (Gen 2, 2025)	Earbuds	Auracast via update — verify before buying	Low-Med	~300

🚫 Out / not yet: Sony WF-1000XM5 (designed too early), Apple AirPods (no Auracast at all), most pre-2024 earbuds.

Market shape: Real but young — crossed from promise to shipping ~mid-2025. Leaders: JBL, Samsung, Sennheiser, Technics, Google. Budget breakthrough: EarFun (Auracast under €100). Catch: many got it via firmware — always check the maker's app.

🎯 For your 3-headphone goal: all 3 must be Auracast and the phone must broadcast Auracast (verify OxygenOS — likely needs v15) or use a C82 Aura transmitter. Cheapest 3-Auracast route ≈ 3× EarFun Air Pro 4+ ≈ €270 — versus a €10 wired splitter that already does 3 with your current assorted headphones.

⚠ Verify these on YOUR OnePlus 12 first

Two things on this page depend on your exact OxygenOS build and your headphones — don't take them on faith, check:

Open Settings → Bluetooth (and Settings → Connection & sharing) and look for "Auracast", "Audio sharing", or "LE Audio". If it's there → option ① is live for you.
If you're not on the latest OxygenOS, update the phone (Android 15 / OxygenOS 15 added broader Auracast support) and re-check.
Check each headphone's spec for "Auracast" or "Bluetooth LE Audio". No mention = it won't receive an Auracast broadcast → use option ② or ③.
Confirm whether OxygenOS shows any "dual audio / second device" option — if so, that covers 2 of your 3 for free, but you still need ②/③ for the third.

Tell me what the Settings screen shows + your 3 headphone models and I'll lock in the exact one to buy.