I am looking at getting this NVR (DS-7608NI-I2/8P)(8 Port with PoE model) but concerned about the fan noise. I know completely silent is not possible, but how noisy is this unit? It will be placed in a room near a bedroom. Just want to make sure it is not noisy enough to become annoying. If the NVR turns out to be too noisy, are there any fan mods you can do with this unit like those mentioned in this thread?: https://www.ipcamtalk.com/showthread.php/7714-Replacing-Fan-In-Hikvision-DS-7608NI-E2-8P-NVR