How We Research
We compare products from their published specs and features; the verdicts below are our independent editorial opinions.
If you want a plug-and-play USB-C transmitter that turns a PS5, PS4 or computer into an aptX HD listening station for the earbuds and headphones you already own, choose Middle Rabbit D1; if you need a travel adapter that pulls audio out of an airplane seat's 3.5mm jack and pushes it wirelessly to your headphones, choose Avantree Relay & Voyager.
• Middle Rabbit D1 — biggest strength: a USB-C dongle built around Bluetooth 5.4 and a Qualcomm chip, with aptX Adaptive, aptX LL, aptX HD, aptX and SBC support plus latency figures spelled out (as low as ~40ms with Adaptive/LL, ~60ms standard aptX, ~100ms aptX HD).
• Middle Rabbit D1 — biggest trade-off: it needs a USB-C host (console, desktop or laptop) and it does not work with Xbox or PS Portal, nor does it support Linux.
• Avantree Relay & Voyager — biggest strength: a self-contained, battery-powered travel adapter with a 3.5mm AUX input, an OLED display, aptX Adaptive and aptX Low Latency, and Bluetooth 5.3 — made for airplane entertainment systems and gym equipment.
• Avantree Relay & Voyager — biggest trade-off: its input is a 3.5mm AUX jack, so it is not compatible with phones, car stereos or hearing aids, and it isn't a USB transmitter for a console.
• Who each is for: Middle Rabbit D1 → gamers and desktop/laptop listeners who want aptX HD from a USB-C port. Avantree Relay & Voyager → frequent flyers and travellers who want to use their own Bluetooth headphones on a plane.
The D1 is, at heart, a codec-first product. Middle Rabbit built it around aptX Adaptive, aptX LL, aptX HD, plain aptX and SBC, and the adapter automatically selects the highest codec your headphones support. That single design decision is the whole pitch: if you own a pair of aptX HD earbuds or headphones — or AirPods Pro 2, which the listing explicitly names as compatible — you're not buying new audio gear, you're buying a way to feed the gear you already like from a source that normally refuses to talk to it.
That makes the PS5 and PS4 the headline use case. Consoles don't natively stream to Bluetooth headphones, and the D1 solves that with a no-driver install: plug into USB-C, put your headphones in pairing mode, pick "Middle Rabbit D1" as the audio output, done. The 40ms latency window with aptX Adaptive or LL is the number that matters here, because it's the difference between dialogue landing on the lip movement and not. For single-player games, streaming apps and late-night movie watching, that's a clean setup. The same logic applies to a desktop or laptop PC running Windows or macOS, which turns the D1 into a general-purpose aptX HD dongle for music listening — and Middle Rabbit specifically calls out crisp highs and deep bass when aptX HD is active, which is the kind of claim you can only evaluate against your own headphones.
There's a real caveat hiding in the spec sheet, though, and it's worth reading twice: call mode. The D1 can activate your headset's microphone, but audio quality drops significantly in that mode, and Middle Rabbit itself advises against using it during gaming or movie playback. So this is not a headset replacement for competitive voice chat. Buy the D1 for listening, not for talking.
Avantree Relay & Voyager: Who It's For
Where the D1 is a console dongle, the Relay & Voyager is a travel tool, and its input tells you everything: a 3.5mm AUX jack. That jack is what lets it hijack the audio from an airplane seat-back entertainment system — a source that has no Bluetooth of its own — and rebroadcast it to your AirPods, Bose or any other Bluetooth headphones. Avantree has been in wireless audio for two decades, and this product reads like it was designed by people who've spent a lot of hours on long-haul flights.
The spec sheet is unusually transparent about what it won't do, which I appreciate: it's not compatible with phones, car stereos or hearing aids. So don't buy it thinking it's a universal Bluetooth transmitter. It's an AUX-in transmitter for headphones, full stop.
The controls are the second half of the story. On-device buttons handle volume, pairing, reconnecting and clearing pairing history, and you can check battery level without reaching for a phone app. The OLED display is the standout detail — it's a genuine quality-of-life feature in a dark cabin or a noisy gym, because you can see connection status and battery state at a glance instead of guessing from a blinking light. LED indicators back that up. Power comes from an internal battery, which is what makes the whole thing work away from a wall outlet, and the unit is described as lightweight and pocket-sized, with travel and gym sessions called out as the intended scenarios.
Codec-wise, the Relay covers aptX Adaptive and aptX Low Latency on top of Bluetooth 5.3, so when your headphones support those codecs you get high-quality audio at low latency — relevant if you're watching a movie on a seat-back screen and don't want the sound trailing the picture. The Qualcomm chipset underpins that.
Who should skip it? Anyone who wants to wirelessly connect headphones to a PlayStation, Xbox or PC — that's the D1's job, not this one. Anyone expecting phone or car stereo support. And anyone who needs a microphone path, since nothing in the sheet suggests the Relay handles voice input.
• Best for console gaming audio → Middle Rabbit D1. Bluetooth 5.4, Qualcomm chip, aptX Adaptive/LL down to ~40ms, and a USB-C install with no drivers.
• Best for airplane and gym use → Avantree Relay & Voyager. The 3.5mm AUX input is the entire reason this product exists, and the battery power means it works anywhere.
• Best for aptX HD music listening from a PC → Middle Rabbit D1. aptX HD is explicitly supported and the adapter auto-selects your headphones' best codec.
• Best for on-device control and status visibility → Avantree Relay & Voyager. OLED display plus volume, pairing and battery-level controls on the unit itself.
• Best for latency-critical video sync → Middle Rabbit D1, purely because it publishes specific figures (~40ms / ~60ms / ~100ms depending on codec) and lets you reason about your own setup.
• Best for portability → Avantree Relay & Voyager. Battery-powered and pocket-sized by design; the D1 needs a host device with a USB-C port.
• Best for voice chat and headset mics → neither, honestly. The D1's call mode degrades audio quality and isn't recommended for gaming or movies; the Relay's sheet doesn't describe a mic path at all.
• Best if you own Xbox or use a PS Portal → neither. The D1 explicitly excludes both.
In my opinion, if I had to pick one for the most people, I'd take the Middle Rabbit D1 — but only because the aptX HD headline is a console-and-PC problem, and the D1 is the one that actually solves it with a plug-in dongle and a published latency ladder. If your life is flights and hotel gyms rather than a PS5, flip the recommendation entirely: the Avantree Relay & Voyager is the more self-sufficient device, with its own battery, OLED display and AUX input. Buy the one that matches your source device, not the one with the longer spec list. And check the current price on Amazon before deciding, since value is the one thing a spec sheet can't tell you.
aptX HD has to be built into the headphones themselves — it's a codec licensed per device, not something an adapter can add. The D1 supports aptX HD on its side and automatically selects the highest codec your headphones can handle, but if your earbuds only do SBC or AAC, you'll get SBC. Middle Rabbit names AirPods, Sony, Bose and Sennheiser as compatible headphone brands, though compatibility and codec support are separate questions.
Do I need aptX HD for gaming, or is low latency more important?
For gaming, latency matters more. Middle Rabbit lists ~40ms with aptX Adaptive or LL, ~60ms with standard aptX and ~100ms with aptX HD — so chasing HD can actually cost you responsiveness. If you're gaming, let the adapter pick Adaptive or LL. If you're listening to music, aptX HD is the better trade.
No. Avantree states the Relay is not compatible with phones, car stereos or hearing aids. Its input is a 3.5mm AUX jack designed for sources like airplane seat-back entertainment systems, and it outputs to Bluetooth headphones. Treat it as an in-flight and gym accessory, not a general-purpose transmitter.
No — the D1 is explicitly not compatible with Xbox or PS Portal. It works with PS5, PS4, and desktop or laptop PCs running Windows or macOS. Linux is not supported either, so check your platform before buying.
As an Amazon Associate I earn from qualifying purchases.
We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon and affiliated sites.
When you buy through links on this page, we may earn a commission from qualifying purchases at no extra cost to you.
Amazon and the Amazon logo are trademarks of Amazon or its affiliates. This site is an independent third-party review and is not affiliated with, endorsed by, or sponsored by Amazon or the product brands mentioned.
See also: EarFun Air Pro 3 vs Avantree Relay & SoundJet: APTX Adaptive, SONY WH-CH520 vs Middle Rabbit TK01, Plantronics Voyager Legend vs Remtise Acoustic Tube Earpiece