Winix A230 HEPA 4-Stage Air Purifier

As a long-time owner of a Winix 5500 that has operated nearly 24/7 in my living room for many years without issue, I thought it was time to upgrade my bedroom air purifier to a Winix product as well. However, I'm pretty underwhelmed by the product. I'll hit you with the Pros and Cons if you're short on patience, but go into further details after if you're curious: PROS: - Competitively priced for the performance it provides and sq ft coverage it provides - 1-year filter life, cutting down on waste and costs CONS: - Bearing noise - Motor noise - Fan imbalance - No way to turn off the air quality indication light when the unit isn't in sleep mode Details: Because my aforementioned Winix 5500 has been so reliable and whisper quiet for so many years, I was confident going into my purchase of this smaller Winix for my bedroom. However, after living with it for ~2 weeks now, I'm pretty underwhelmed by the unit in terms of quality and noise. The major problem I have is the fan inside the unit itself. Right off the bat, upon turning the unit on, you'll notice a moderately high-pitched scratching or scraping noise, which I can only describe as bearing noise. It sounds like the fan uses a ball-bearing setup, which is very robust and reliable, but results in the noise described above. Additionally, the motor that drives the fan hums. These noises are present at all speeds, regardless of Plasmawave being enabled or not, and only the motor noise fades off in sleep mode. I was actually so surprised by this medley of off-putting noise, especially because NONE of the reviews mentioned this, that I contacted Winix. After sending a video, they determined that the unit was defective. Upon receiving my replacement unit, I was disheartened to hear that this unit exhibits the same exact noises. It's not a defect, that's how this thing is designed. See an attached picture of the waterfall graph to see empirical evidence of these noises. The graph (purple in color, from bottom to top) starts with the unit being off. You'll notice as soon as I power the unit on, the high pitched noise appears around 2 KHz, and the motor noise around 500 and 600 Hz. You can also notice the intensity of said noise, most notably the motor noise, increasing as the fan speed does. The next jump is when I disable automatic fan speed and set it manually to Low, then another jump when it's set to medium. Additionally, you can also feel the fan moving within the unit when not in sleep mode, as if it's imbalanced. It's not a buzz, but a wobble. You can feel the entire fan wobbling around inside of the case. I live in a city and the white noise that fans and air purifiers provide help sleep through the hustle and bustle and sirens outside overnight. Sleep mode on this unit is very quiet which is nice, but too quiet for my needs. Because of this, I tend to never use sleep mode which means two things: Noise and the AQI light remaining lit all throughout the night. Fine, I can cover up the light, but then there's the noise. So, I have to run the fan at the medium setting so that the sound of the airflow drowns out the motor and bearing noise. The purifier does it's job of cleaning the air, it makes a noticeable difference in the air quality and smells fresh in my bedroom. Unfortunately, it doesn't live up to the standards I had for Winix based off of my experienced with their other units. At first I thought it was a QC issue, but it's actually just poor component choices and design. Hence the 3 stars. I won't be returning the unit, because I like the filtration performance and I can live through the noise it generates, but if you're looking for silent operation or a pleasant white noise machine, look elsewhere.