Just got S5 and it is hashing steady. The noise is not bad. From the reviews I thought it was going to be much louder. Its a higher pitch for sure, its small in size and not really overwhelming. I have one setup in my bedroom and don't think it will be a problem.
I'd suggest you get your hearing checked.
Mine is in the sub level basement garage of my apartment building, and anyone who walks down to the basement garage can hear it (my garage is the furthest away in the basement)
dB readings:
Standing outside my garage door - 7meters from it - garage door, car, a wall of boxes between me and the S5: 59dB
1meter direct line of sight from the S5: 69dB
1foot above the S5: 77dB
The heat sink exit metal temp reading is only 39degress - so maybe the fan is over compensating? ...