Should I be concerned?

[Zoomie]

I have had my PowerTig 225LX now for about three months and I have noticed something unusual. When I first began using the machine the amperage on AC could be set down to about 22 and any increment from 22 up to 227. Now I am still able to set the amperage as low as 22 but there appears to be a dead spot between 22-31 or so. Ie, it wont adjust to any setting in that range on the panel. I have the pulse off with no upslope or downslope dialed in. The foot pedal seems to also mimic the problem. Any ideas? Also when you weld and stop the welder it will initially show 30 and then click back to whatever you originally had set. Oh, on DC it seems to adjust normally...