Windows or Mac ? What version and what driver version ?

The main difference between the two interfaces :
Scarlett is a minimum channel interface, Babyface is a multichannel interface with 24 channels.

Is your computer a Notebook ? There are lots of optimizing tips for music-computers out there.
Switching off any power saving management especially USB-power saving options is what I remember but there is many more.
Also every DAW has its optimizing options, whats your DAW ?

Is the project overfilled with plugins ?
128 buffer should be no problem.
If you run a new empty project with only one song, is this playing without pops ?

A system with that CPU should easily be able to work with a 188 channel interface like the UFX III
up to a 390 channel interface like the HDSPe MADI FX.

Try all USB ports

Did you try already all USB2 and USB3 ports on your system?
Normally, all USB3 chipsets should be 100% backward compatible to USB2. Each USB3 port has separate pins for USB2.
Usually, there are no USB chipset issues under USB2 I read here from RME on the forum, USB3 is more demanding.
But what can always happen is that two USB ports share the same USB controller, and this can be bad for a recording interface. Therefore, disconnect all USB hardware that you do not require and try all USB2 and USB3 ports for connecting the Babyface and check whether the situation becomes better with one of these ports.

If that does not help, check the settings and DPC Latencies as described below. But here is a recommendation if you have a Desktop PC and a free PCIe (2.0 x1) socket which does not share PCIe lanes with another PCIe socket or M.2 cards:
To really ensure that the recording interface gets a dedicated USB controller for itself, I would suggest getting an additional USB3 PCIe card for your system with FL1100 USB3 chipset on board. This card/chipset s known to support USB3 and USB2 recording interfaces very well. Its drivers are integrated with Windows 10 and 11 already and work with the more efficient interrupt scheme called MSI (Message Signalled Interrupts). This hard here:
https://www.sonnettech.com/product/alle … 4port.html

Check DPC Latencies

Did you use LatencyMon to check whether your PC is suitable to handle real-time audio processing?
https://www.resplendence.com/latencymon
Under Tools -> Options -> Tab "General" set to measure
   [x] Interrupt to user process latency
Run it on a freshly started and IDLE system for at least 5–10 minutes.
Wait a couple of minutes after login until startup- and login- related processes settled, and CPU activity goes down.
Do not start any other application as it induces already a DAW load to your system.
During measurement, avoid mouse and keyboard activity.

Energy Profile

Do you use High-Performance or even Ultimate Performance energy profile?
See: https://www.howtogeek.com/368781/how-to … indows-10/
    powercfg -duplicatescheme e9a42b02-d5df-448d-aa00-03f14749eb61

Windows Memory Integrity (VBS) disabled?

Is Memory Integrity (VBS) disabled? It is a security feature, but is badly "overdesigned" for end users' demands.
Therefore, Microsoft has blocked installation of Win11 on older systems where it is enabled by default because
there is not enough performance left. But even on modern systems, gamers (who also need a fast reacting and
performant system) complained about lower fps so that Microsoft had to invent the gaming mode which disables it.
https://www.tomshardware.com/how-to/dis … windows-11

BIOS Settings, disable energy savings

Is your BIOS tuned to turn off energy saving to get a quicker reacting system with lower DPC latencies?
- Disable C-States or set to C0: keeps CPU cores active even if they are not in use, reduces DPC latencies a lot
On some systems, you can also disable P- and T- states, to keep the CPU running at a constant frequency
and to disable thermal throttling.
- Disable C1E (enhanced halt state) so that the CPU core does not lower voltage and clock frequency to save even more power
- Enable Turbo (allows CPU to boost its clock speed beyond the base frequency when thermal and power conditions permit)
- Keep EIST enabled, you can control CPU clock speed by Windows Energy profiles.
- Disable "Spread Spectrum" to avoid changes of the CPUs clock frequency, as a settling time is required for the new clock frequency to stabilize. This can cause some µs of lag which we better save for lower DPC values.

Optimization for background processes

Check whether this brings you benefits. It sets the time quantum of the process scheduler to a longer and fixed time quantum like in Windows Server to be able to work on processes more efficiently:
https://www.tonstudio-forum.de/blog/Ent … es-or-not/

Backup before doing changes

It is highly recommended to perform a backup of your system and - if you change BIOS settings - to make photos of your BIOS settings before changing anything.

Macrium Reflect Home is an excellent disk imaging software.
I would purchase the tool as the demo version is lacking two important features.
- RDR (Rapid Delta Restore, see https://blog.macrium.com/focus-on-macri … 3a244a0fb)
- incremental backups

With Rapid delta restore, only the deltas/changes are restored which increases restore time massively.
I can restore a 1 TB SSD filled with around 850 GB of data in less than 15 minutes.
So if you perform a few changes and want to go back to the previous state, it does not take much time and it is reliable.
I would not trust Microsoft tools, they are lacking such features and helpful options.

If you buy four Macrium Reflect Home licenses, then you get 2 for free. Ask your friends and in family, then you save 50% of the price for one license.

Hello

Agree! Your BF Pro FS should work as well or better than your Scarlett at 128 samples, IMHO the reason is between DAW↔OS↔RME USB Driver and it should be something very simple, the difficult thing is to know what fails in the fastest way, at least for users like us. I've also changed from Clarett 4Pre to UCX II and (not being an expert in the matter) observed that the USB technology used by both cannot be compared.

You've paid for new hardware and a software license, why not ask RME and Ableton what's going on? Seeking help here is always a good idea (you may find the answer here ... or not) but backed up by qualified support would be better, that's what I would do.

It will be a pleasure to read your discoveries

Does this make really sense to you? Look at his CPU how performant it is.
This should be more than sufficient for any RME recording interface.
And the difference between a Scarlett and BBF Pro might at maximum only be 20 channels.
If I compare this with my 188 channels ...

My CPU is 3-4x slower compared to his CPU, but I can use an UFX III with 188 channels without issues at 32 samples ASIO buffer size. Even with 400 channels and 2 VST per channel, in total 800 VSTs. Also at 96 kHz.
See https://www.tonstudio-forum.de/blog/Ent … cks-de-en/

To draw another comparison, the MADIface Pro (from 2016) had alone 68 Channels via USB2, and it worked also pretty good years ago on systems which had at that time (2016!) significantly less CPU power compared to his system.

I think there is something different wrong, I wrote already a lot what he could check.

Only because you have a performant system doesn't mean you can use as many VST as you like.
Some VST and VSTi use a lot of system resources, which can make it necessary to choose a much higher ASIO buffer size.
For example iZotope Ozone.

I would wait now for more details from him, I think we speculated already enough.

After running through all of these steps and a lot of others around the web. I think I have it running smoothly now. Hopefully this helps someone. The link is here: https://www.reddit.com/r/techsupport/co … _ntoskrnl/

The steps that fixed it for me:

Download PowerSettingsExplorer from here and run it as administrator. Then find the following 2 options: Processor Idle Demote Threshold and Processor Idle Promote Threshold, UNtick them both, then go to your power plan settings, find the new option under "Processor Power Management" and set both to 100%. That helps lower mostly all latencies, if you are happy, you can stop here, if you want to try and lower them even further, please continue.

Unparked all my cores. I used PowerSettingsExporer as described in fix 2, unticked Processor Performance Core Parking Min Cores and then went into the Power Plan Settings and set this to 100%, and boom everything is resolved.

I now have everything in the green in LatencyMon and I can run my big project with 256 samples. Thanks for all the help!