I believe that Steinberg is false advertising the UR-C Audio Interface line of products by irresponsibly NOT supporting the current macOS 15 Sequoia for use with iOS versions of DspMixFx (an integral software part of the interface)
Clearly states that NEW FEATURES
*### Dedicated streaming mix *
dspMixFx now features a dedicated streaming mix with an exclusive effect slot. This slot features effects that can be assigned for streaming purposes only, such as gate, compressor, and ducker. The main output of the streaming mix also features its own multi-band compressor. This mix output is an additional output mix for UR22C, UR24C and UR44C. On the UR816C it can be selected instead of Mix 4.
ALL OF THE ABOVE FEATURES were introduced with UR-C version 3.0 that was introduced in 2024 yet the iOS dspMixFx Remote Bridge HAS NOT BEEN UPDATED since 2022 basically rendering it inoperable for macOS version 15.
Anyone that purchases this interface in 2025 and uses the latest macOS version WILL NOT be able to use the remote bridge which means that dspMixFx for iOS does not work.
Please Fix and/or advise the public in order to avoid user dissatisfaction.