What is wrong with my Jolida 1501RC?

I have a Jolida 1501RC tube/solid state-hybrid amp that I have owned for a little over a month now, Today I noticed a rythmic static in the background on both channels. It seems to come in and out in about 1 second intervals. The volume and/or input selection has no effect over this static. However, when the amp is unplugged for a few minutes and then turned back on the static seems to subside, only to return again after a couple minutes of being powered up. To me this would seem like a power supply issue, but It would be nice to get an opinion before I send it in for service.
Thanks

Joseph M. Leonard