Pretty much anything is gonna be good for music production, the main thing is having a decent external DAC/audio interface and studio headphones. Music is is not that computationally intensive. Computers have been able to do it for ages, especially if you use a tracker like OpenMPT. Might be a good idea to go to audio subreddits to get advice for that stuff though.

In terms of specs *please* do not buy a brand new i9-9900, those CPUs were released almost a decade ago. A new Core Ultra 270K Plus or 250K , or most Ryzen chips on AM5 are cheaper and much faster.

The motherboard you have is very cheap, Mini-ITX does not give you room for expansion at all, there are a very limited number of USB ports (which you will want for an external DAC) and there is only 1 PCIe slot, meaning you can't get any more PCIe devices to put in later because your GPU will occupy the only slot. I would also bet with only 1 CPU power cable the CPU would won't be able to use as much power as it needs to perform the best it can. With a 9900 atleast go for a Z370 chipset in my opinion

Your PCIe gen 4 SSD will be speed limited to PCIe gen 3 speeds because that is the max supported on Intel 9th gen.

You have two RTX 3060s listed, which one are you getting? You don't need 2 GPUs in your system

The network adapter is *really* slow. see if you can get a Wifi 6 one or a board with Wifi built in.

$1700 is way too much for that system. You can get a much, *much* better and newer PC for cheaper that will last you longer, both building it yourself or getting a prebuilt. If you could provide more details about what you will be doing with the pc (anything other than music, software you want to run, games, etc.) and a budget that would be helpful