Here's my hypothesis...

The Audient ID14 is an extremely quiet interface. So the issue isn't with the interface. So let's scratch that off the list.

Regarding the PVC booth, it's generally recommended to have 3 layers (not 2 layers) of moving blankets. So something like this would add 24 POUNDS of blankets for about $49

https://www.amazon.com/Sure-Max-Moving-Packing-Blankets-Professional/dp/B077GF33G1/ref=bmx_1/132-0776120-8240839?_encoding=UTF8&pd_rd_i=B077GF33G1&pd_rd_r=e0465f9c-43c4-11e9-870e-afb0e07225f8&pd_rd_w=xY99H&pd_rd_wg=YXejQ&pf_rd_p=33750cd9-1585-4897-b3e3-d6ba72a2aa24&pf_rd_r=5N5MHEE4RYRNV150XCSM&psc=1&refRID=5N5MHEE4RYRNV150XCSM

As for Rockwool panels, they're an option too but honestly just adding an additional layer, making it 3 layers, would give you the coverage you need. I'm always amazed by PVC booth audio.

You also mention that you aren't getting sound from the laptop fan.

What does that leave you?

It's either the wiring (the wire connected to your ID14)...and I don't think it is....

So maybe it's your mic.

I have no idea about that mic you're using but there's not much information about it online. You can find it used for about $100 but it may be what's causing the issues there.

Maybe as a point of troubleshooting, you can try a microphone with low self-noise (Rode NT1) and see if the problem persists. If things don't change, you know it's something else. But if you get vastly improved audio quality, it's your mic.

But another thing is that sometimes people get so tuned into audio (I've seen it happen) and they think the problems they have are much worse than they really are. Sometimes someone will freak out and post audio they think is bad..and it's actually perfectly fine or nothing a director wouldn't be happy with.

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