The page below is related to the 2480, as there is no listing at Lexmark for a 2400 (it is a series).
Based on the description you have provided, I would suggest several resolutions are possible. If the printer is not powered through a UPS (or other power surge protected power supply), it could very well be caused by power fluctuations. This seems particularly possible given that resetting power alleviates the issue.
It is also possible that there may be a driver issue, especially if this occurs more often with certain types of documents or in particular processes. The page above is for a specific model, and references drivers for that model.
If this is not the proper model, and you can not find the proper model, an online chat (also accessible through that page) could possibly be the quickest way to resolution. Please let us know if you need further help, as there are numerous other sources for drivers, e.g., otherwise thanks for rating FixYa!