If you wanted to dose only 10 mL over lets say six hours at night, this is how often your DOS would operate:
Amount to dose: 10 mL
Time allotted: 359 min
Time used: 97 %
Number of doses: 25
Dose every: 14 min
Volume per dose: 0.4 mL
Volume of last dose: 0.4 mL
Unused time remaining: 9 min
Pump speed: 7 mL/min
**So basically it would do 4 drops (seconds) every 14 mins at the slowest speed possible** i.e. you likely wouldn't notice this
If you were to do 50 mL, then it would operate like this:
Amount to dose: 50 mL
Time allotted: 359 min
Time used: 97 %
Number of doses: 35
Dose every: 10 min
Volume per dose: 1.4 mL
Volume of last dose: 2.4 mL
Unused time remaining: 9 min
Pump speed: 7 mL/min
**Basically it would do 14 drops (seconds) every 10 mins at the slowest speed possible** i.e. you might hear this if you are super noise sensitive. As the motor does create some create a low electronic hum.
If you try to dose more volume over shorter periods of time the the pump speed will be faster. When you get about the 60 mL/min speed you can definitely hear it. Most people only reach those speeds when they are trying to do AWC with the DOS instead of additives.
Hope this helps.