Reason I ask is most consumer UPS's don't give you that clean power unless the input voltage has gone low enough to cause it to switch to battery, under its normal operation the input power is fed straight though, noise, spikes small surges and all.
You may be aware but I find any are not. Basically the lower cost UPS's are the offline also called switching type. Some will incorporate a surge protector in as well, but sometimes, like yours they are separate outlets from the battery backup outlets. Most of these UPS's will switch to battery if the input voltage goes too high as well but spikes and noise are usually too quick to cause them to switch.