@lostintheether
Bluetooth audio lag in Recalbox 9.2 is often due to latency introduced by the Bluetooth stack and audio buffering. While RetroPie may have different kernel modules, drivers, or audio routing configurations that reduce this delay, Recalbox tends to prioritize system stability and may not optimize Bluetooth audio latency by default.
Some common causes include:
Audio backend differences (ALSA vs PulseAudio or PipeWire)
Bluetooth controller performance, especially if using a built-in module vs external USB dongle
Lack of A2DP low-latency codec support (e.g., aptX, AAC, or LDAC not enabled)
CPU resource allocation, since Recalbox is more tightly integrated and may reserve fewer resources for real-time audio processing
This is actually a classic example of hardware-dependent performance in embedded systems. The Bluetooth chipset used (often on Raspberry Pi boards or USB adapters) directly affects signal stability and codec support. Similarly, the audio DAC or SoC may introduce extra buffering if not optimized.
For developers or hobbyists building custom emulation boxes or handhelds, it’s a good reminder:
Choosing the right wireless module and audio output stage matters — it's not just software.
If you’re working with custom hardware or planning to build your own retro console, consider evaluating low-latency Bluetooth modules, external DACs, or even wired alternatives for more predictable audio behavior.
