A few weeks ago we had a discussion about ddhifi 4.4mm ground pin adapter for WM1A/ZM2 DAPs and if it going to fit Dignis case. I just got this adapter in, full spec and info
here. It is offered for WM1A/Z and WM1A/ZM2, in both black and gold finishes for corresponding models. And as many are aware, Sony does not connect Ground pin on their Pentaconn socket, only L+/L-/R+/R-. This adapter from ddhifi "borrows" ground pin from 3.5mm side to have a proper TRRRS grounding and improved shielding. It's a nice slim adapter, solid build, uses 25.5 awg pure copper wires and audiophile quality Mundorf solder. I still need to do more testing, but in a series of blind tests last night (my wife already accepted I'm nuts asking her to conduct these tests), I was able to distinguish IEMs plugged in directly vs through this DJ44S adapter. It's not a night and day difference, but you can hear a cleaner background, and yes, I would have said "placebo" effect, but it was a blind test where I got many of them right.
Now, about the fit with a DAP inside the case. Obviously, no issues with a naked WM1ZM2, and it doesn't stick out too far, looks nice and clean.
Also, with MITER case where the top is not covered, no issues as well. There is a gap like you would see with a naked WM1ZM2.
And, no issues with Dignis case either!!! There is still a tiny gap in there, the top flap of the Dignis case doesn't interfere with an adapter. So, all is good for Dignis case owners who considering getting this 4.4mm ground pin adapter.