Firefly V2 pro issue connecting with Razer Synapse 4

I’m having the EXACT same issue and have gone through the same troubleshooting steps.  I even used CCleaner to clean up my old files and it is still being persistent...

It is also important to note that Razer synapse 3.0 detects the Firefly V2 pro without any issues.  I did some research and the Firefly V2 pro is “supposed” to be compatible with synapse 4.0, but clearly there are some issues with that.

Hello ​@mahoot207, Razer just openned an issue and they are working on it.

I will keep you posted about possible updates

hooked up to my ROG ally, with pre-installed synapse 4, firefly v2 pro didnt show up as well. however it worked well with my laptop with no pre installed synapse 4.  pls help 

It seems that my razer v2 pro cant show up as well.

I am having the same issue with Razer's Synapse v4 software. I have two Razer v2 Pros conected and both appear to be in the circle of death loop trying to be configured with
their worthless software. What is amazing to me is this issue has been systemic with every version of Synapse software and their engineered products. Furthermore, I have just
started using software with by a third-party (SignalRGB) which is used to control and customize the RGB lighting on my computer and peripherals from numerouse manufacturers. 
This software work flawlessly with my Razer keyboard, Firefly mouse pads, Logitech game pad (G13), NZXT fans, Gigabyte 4090 GPU, MSI Motherboard, Lian Li Streamer Plus and etc...

Now here Razer who is engineering the mousepad and keyboard they claim their software is desigend for doesn't work. How lame is that? Maybe the worthless coders for Razer 
should contact SignalRGB.com and discover their success. LMAO....

I have the same problem as you, it only shows an infinite circle. I've already tried everything

Been following up with them on a daily basis about this since December, so far it has been, “Check if everything is up to date”, “Oh we have an update!  What is that?  It doesn’t work?  Try all the diagnostic tips we mentioned plenty of times all over again!”, “Show us the log, looks like you have to reinstall/check everything again.”  Things like that, and if you don’t respond with 24/48 hours, they will be very quick to close your ticket and assume things are resolved.  I say keep bugging them about this, they will eventually get flooded and move it up their priority list.  I have quite a log of how this specific issue has been going.  So far I have tried:

File swap between laptop to PC, no luck

Admin mode crap

Literally everything Razer has explained to you on what to do (fourteen separate times)

I have spoken to 9 different people on the Razer support team, across from 45 different emails.  The issue you are experiencing, that I also am experiencing, still persists.  

I will not say who I spoken to specifically as I will respect their privacy, that being said, it is honestly frustrating the program is failing to work as intended, while it works on the laptop just fine.  

While I am relieved I am not the only one experiencing this issue with this mousepad and Synapse 4 specifically, I am more annoyed and frustrated on how the support team is handling this.  I can understand the engineering team (or coders) are having a difficult time figuring out what is wrong, as a consumer, I can’t quite say I can recommend this company to anyone because of the programming errors.

I have verified Asus Armory Crate, Glorious, G.Skill, Lian Li, AI Suite, MyAsus, and Nvidia apps (or exe), aren’t the reason why Synapse 4 won’t work.  I have tried going back to Synapse 3, but that won’t recognize the Blackwidow V4 75% pro.

What I run:  i9 14900K, 64GB DDR5 memory, ASUS RTX 4070TIS.  Razer’s Blackwidow V4 75% Pro, Trinity, Nommo V2 speakers w/ Sub, Kiyo webcam, Firefly V2 Pro (the problem child). 

Razer Firefly V2 Pro released April of 2024, Synapse 4 came out September of 24.  Signs I am seeing are pointing to a coding error within Synapse 4, While I do hope the team can fix this soon, the time between September until now (February of 2025) seems quite excessive.  I will be sharing this on Reddit as well since this information needs to get out to everyone so in case if they run into the issue, to be aware of it.

Strider chroma also has the same problem.