bsnes nightly adds CX4 timing fixes as HeatXD enables five-player netplay

Mid‑February brought two linked but separate moves across the SNES emulation scene: the official bsnes project published a nightly build on 2026-02-16 that specifically lists "CX4 timing fixes," while HeatXD pushed a netplay-focused update tagged "Netplay Release V2.HF2" that adds multitap and the ability to run netplay sessions with up to five active players. Users seeking five‑player online matches must run HeatXD’s fork; the main bsnes build does not include these netplay upgrades.

The official bsnes nightly is narrow in scope in the supplied notes: the release artifact published on 2026-02-16 is called out for the CX4 timing fixes and no other official changes are listed in the provided materials. That single explicit change, timing work on the CX4 co‑processor emulation, appears to be an accuracy/bugfix update from the bsnes maintainers rather than a netplay or multiplayer feature rollout.

HeatXD’s announcement opens plainly, "Hey everyone!" and continues with the headline claim: "After a lot of hard work, multitap support is finally here, meaning netplay sessions now support up to 5 active players!" The release header reads "Netplay Release V2.HF2" and the GitHub metadata shows the CI/commit identifier `@github-actions '0715c67'`. The release text lists session stability work, spectating improvements, a redesigned netplay setup window, and crash fixes, and it concludes with the signoff "Have fun! -Heat".

Practical setup details and warnings accompany HeatXD’s build. Dustloop instructions state bluntly, "You must use HeatXD's version of BSNES, the main version does not have these upgrades to SNES netplay. To connect, all players must be on the same version of BSNES." The GitHub release repeats strict disclaimers in caps: "YOU NEED TO HAVE THE EXACT SAME GAME OR YOU MAY DESYNC" and "DON'T CHANGE SETTINGS WHILE NETPLAY IS RUNNING, MAY CAUSE DESYNCS." For audio lag mitigation both sources recommend lowering samples: "IF YOU EXPERIENCE AUDIO DELAYS YOU MAY LOWER THE SAMPLES (E.G. 128 SAMPLES)" and Dustloop gives the path Settings -> Drivers -> Audio to set latency to 128. Dustloop also advises networking steps: "Forwarding a port is the best method of connecting to an opponent. Atleast one player must have a forwarded port..." and suggests choosing a local port number over 10000.

Spectating received a targeted hotfix in V2.HF2; the release emphasizes in caps, "THIS HOTFIX IS SPECIFICALLY FOR FIXING SPECTATING SO PEERS BESIDES PLAYER 1 CAN BE USED AS A SPECTATOR HOST." Dustloop documents how to add spectator slots and enter IP and port and notes spectating has been "hit or miss" historically, which the hotfix aims to address.

Platform caveats are explicit. The GitHub release warns "LINUX ONLY: If you experience extremely high framerates, try this fix: bsnes-emu#324 (comment)" and "MAC ONLY: The Mac build seems to have broken rendering on macOS (at least on my M1 Mac), so it's highly likely the Mac build doesn't function properly." The captured GitHub page also shows UI load messages such as "Uh oh! There was an error while loading. Please reload this page," which appear in the raw capture.

Community coverage frames the split between official accuracy work and community netplay innovation. Timeextension notes HeatXD’s fork is integrated with GekkoNet and that "HeatXD released the initial build (V1) on GitHub last July" and "returned with a second build (V2) this past weekend, introducing multitap support," adding that "this means it is now possible to play with up to five players on games that originally supported the option, including titles like the 1997 Japan‑exclusive Bomberman game, Super Bomberman 5." Dustloop calls the BSNES rollback from HeatXD "By far the most consistent and well implemented."

The immediate takeaway is concrete: if you want five‑player SNES netplay, download and run HeatXD’s Netplay Release V2.HF2 and keep every participant on the same game build and emulator version; if you are tracking accuracy fixes, note the official bsnes nightly from 2026-02-16 for CX4 timing fixes. Remaining verification items include exact download binaries, the link for the Linux fix reference bsnes-emu#324 comment, and real‑world tests of CX4 fixes and five‑player stability across titles.