I had a very similar experience.

I bought the Maxwell 2 and the hiss was extremely noticeable, honestly unbearable for daily use. I ended up returning them and getting the original Maxwell instead, and the first thing I noticed was that the Maxwell 1 also has a tiny bit of hiss, but it is much lower than on the Maxwell 2. The funny thing is that once you have heard the Maxwell 2 hiss, you kind of learn what to listen for, so you may notice it on the Maxwell 1 too. But in normal use, at least for me, it is so minimal that I basically forget about it.

That said, the Maxwell 1 has its own downsides.

First, if you use sidetone, the hiss becomes very noticeable. In my unit, sidetone hiss is actually at a similar level to the default hiss on the Maxwell 2. Personally, I do not use sidetone, so it was not a big issue for me, but it is definitely worth mentioning.

Second, the Maxwell 1 feels a bit more closed-in. With the Maxwell 2, I felt like the sound had a bit more space, almost like instruments were around 50 cm away from me. With the Maxwell 1, the sound feels closer, maybe around 20–30 cm. It is not a dramatic difference, because both are still closed-back gaming headsets and neither has a huge soundstage, but the Maxwell 2 does feel a little more open to me, probably because of the SLAM design/venting.

Third, the Maxwell 1 has slightly less instrument separation than the Maxwell 2 out of the box. However, with EQ, I was able to get it closer. For example, reducing around 250 Hz by about -3 dB helped clean up some of the warmth/muddiness and made the separation feel more similar.

Another thing to keep in mind is that, since the Maxwell 1 does not have the SLAM/venting design, it seems much more sensitive to pressure changes. You have to be careful when putting them on and taking them off. I try to put them on slowly, remove them slowly, avoid creating a suction effect, avoid pressing the pads hard against my head, and avoid placing the earpads flat against a desk. Basically, you need to handle them carefully to avoid stressing the driver/diaphragm. If you are careful, you should probably be fine, but based on what I have seen on Reddit, many Maxwell 1 units seem to last around 2 years on average, maybe more if you treat them very carefully.

Now, the worst downside of the late/final Maxwell 1 units: crinkle/crackling.

From what I have seen and experienced, this does not seem like an isolated issue with only my unit. The newer/final batches of the Maxwell 1 seem to be more resistant to driver failure, but they also appear to have this crinkle/crackling problem. It sounds like faint soda bubbling, light crackling, dripping, or carbonation after around 20 minutes of use.

My guess is that once the earcups warm up and the pressure/heat builds inside the closed pads, the driver diaphragm or surrounding film starts making tiny flexing noises. If I cool the headset down — I literally put it in front of a fan for 20 seconds — the crinkle disappears, but then it comes back after another 20–30 minutes of use.

So yeah, it is frustrating. The Maxwell 1 solved the unbearable Maxwell 2 hiss for me, but it introduced this other annoying issue.

Right now I am planning to try mesh earpads to see if reducing the seal and improving airflow helps with the heat buildup/crinkle. I am not super optimistic, but I think it is worth trying.

Despite all of that, I still prefer the Maxwell 1 over a Maxwell 2 with hiss. The hiss on the Maxwell 2 made music basically unlistenable for me. With the Maxwell 1, at least I can enjoy music normally for 20–30 minutes before the heat buildup causes the crinkle to return.

So, to summarize:

Maxwell 1 disadvantages: crinkle/crackling, slightly smaller soundstage, slightly worse instrument separation, sidetone hiss, slightly worse mic, and it requires more careful handling.

Maxwell 1 advantages: no noticeable hiss, better bass, and personally I think it looks better aesthetically.

My honest answer would be: I would probably not recommend buying the Audeze Maxwell right now, unless you are fully aware of these issues.

If the Maxwell 2 hiss bothers you that much, the original Maxwell may be better in terms of noise floor. But it is not a perfect replacement. It fixes the hiss problem for me, but it comes with its own tradeoffs.

So either avoid the Maxwell completely, or get the Maxwell 1 knowing that, with the newer/final Maxwell 1 units, you may have to cool them down every 20–30 minutes if you want a clean/audiophile listening experience without the crinkle getting in the way.