Independent guide: ZoneFoundry is not a Sonos product. Compatibility changes with products and software, so check Sonos' official compatibility tool before acting.
Before you start
- Write down every Sonos product you own with its model and rough purchase year. Without that list, every step below is guesswork.
- Run Sonos' official compatibility check rather than relying on memory or a forum post. The compatibility list changes.
- ⚠️ Some steps here are irreversible. Downgrading back to S1 is generally not possible, and a system you split may not recombine exactly as it was.
What does having "two systems" actually mean?
This is not two modes of one system. These are two independent Sonos systems, each with its own rooms, its own service authorizations, and its own app. They sit on the same Wi-Fi but do not recognise each other at the software level. Once that clicks, every limitation below stops being surprising — they are not bugs, they are two systems that were never connected.
How do I tell which system each product is on?
Before any decision you need an accurate inventory. Guessing from the product name usually goes wrong: one product name can span several hardware generations, and compatibility is decided by the internals, not the name.
Use the official compatibility check, not memory
Sonos provides an official system compatibility check that tells you directly which products in your system can move to the current platform and which must stay on S1. That is the only authoritative answer. Forum posts and comparison tables from a few years ago go stale, because what Sonos supports shifts with software releases. Run it once and write the result down.
Different software version numbers are normal
If what you have is a mixed but still unified system — older and newer products all still on the current platform — you will see different software version numbers on different products. That is not a split system and does not stop them grouping and playing together. Sonos now ships separate builds to modern and older products. Rushing to reset because the version numbers differ is a common self-inflicted wound.
Confirm you really do have two systems
A genuinely split system has one unmistakable sign: you need two different apps to see all your rooms. If a single app shows every room, you have one system and none of the cross-system limits below apply to you — whatever grouping or playback problem you are chasing has another cause, and you should be looking at the network and your services instead.
Which limitations are permanent?
- Cross-system grouping. An S1 room and a current-system room cannot be placed in the same group, and no setting changes that.
- Cross-system stereo pairs. Both halves of a pair must be on the same system and be compatible models.
- Cross-system home theater. Surrounds and a Sub must be on the same system as the primary speaker.
- One app for both. You need two apps and manage each system separately. That is by design.
- Downgrading back to S1. Once a product has moved up to the current platform it generally cannot go back to join an S1 system. Decide before you upgrade whether you need that unit to stay paired on the S1 side.
These you can actually fix
Service accounts interrupting each other
Each system holds its own service authorizations, but if you use the same music account and its plan allows only one stream, starting playback on the S1 side will cut off playback on the current side, and vice versa. That is not a system conflict — it is the music service's single-stream limit. Two ways out: move to a plan that permits multiple streams, or give each system a different service account.
Voice services need separate setup
Voice configuration is bound to a system and does not carry across. An assistant you set up on the current system will not appear on S1 rooms, and S1 supports a different set of voice services anyway. To have voice on both, configure it separately in each system and accept that the capabilities differ.
Direct-control lists show rooms from both
Some third-party apps build their direct-control device list from local network discovery, which does not respect system boundaries, so rooms from both systems appear in one list. It looks like the two finally connected — they have not. You still cannot group across them. Naming rooms with a system marker, such as a suffix on the S1 rooms, prevents a lot of confusion.
Configure the music library twice, with different requirements
Both systems need the local music library added separately, and crucially they require different sharing protocol generations: the current platform uses newer SMB while S1 needs the legacy version. Many NAS units now disable the legacy protocol by default for security, which is the usual reason newer speakers can read the library and older ones cannot. Supporting both may mean enabling both protocol generations on the NAS — that carries a security cost, and whether it is worth paying is your call.
What are my options, and how do I decide?
Three paths with very different costs. Stay split. Free, but you live with two apps and no cross-system grouping. When the older gear sits in secondary rooms such as a garage or balcony, this is usually the rational choice. Move everything eligible up. Migrate every product that qualifies for the current system and leave only what genuinely cannot move on S1. Worth doing when most of the house qualifies. Replace the old units. The most expensive path, but it buys one complete system that can group across the whole home. If the older gear happens to sit in a primary room like the living room, the long-run cost of working around it may exceed the cost of replacing it.
Do not use a factory reset to "merge" the two systems. It will not make incompatible hardware compatible. It will wipe room names, groups, stereo pairs, home theater bonds and every service authorization — and you will still have two systems, only now you have to configure both from scratch. Run the official compatibility check first and let it tell you what can genuinely move.
Official references
- Sonos app version compatibility
- Set up separate S1 and current Sonos systems
- Known limitations with separate systems
- Update to the latest Sonos app from S1
- Use a NAS drive with Sonos
Once the network is fixed, the daily part can get easier
Grouping, skipping tracks, adjusting volume — that is the part you actually repeat every day. ZoneFoundry is an iOS app that handles those in one sentence. It works with your existing Sonos; the Bridge is an optional upgrade, not a requirement.
Next
The full S1 vs current comparison →
Other reasons grouping fails →
Music service won't connect or play →
ZoneFoundry targets current Sonos control capabilities. It cannot merge S1 with the current system and does not bypass any of the platform boundaries above.