Static from tubes

After watching and listening to some reviews I decided to purchase a Schiit Audio Freya plus preamp. I replaced the Tung-Sol tubes with General Electric GTBs and at least in my system, the separation of instruments was better. This was in March, 2019. I was quite happy at first. Twice, here was some static right after the tubes were changed, then it disappeared. At this point I am again getting static when I use the tubes. I looked inside and the inserts look pretty cheap (plastic).  Is static common with tubes, or is this unit just have this one part of it that is cheap? I am trying to decide if there is a tweak or repair for this, or if I should just sell it cheap and move on. Any ideas?