EL34 glowing internally with signal...

[liquidair]

Hi all, I have a project where I'm using EL34s (new Mullards) and I noticed that as I played I could see an orange glow through the hole in the plates that would pulse with the music. Is that normal? This amp has a b+ around 400-410 at idle and I have 1k 10W resistors on the screens (drawing ~5mA at idle), and I'm biased rather cool at 32mA. I don't really think I'm pushing it, but the screen resistors are getting pretty darn hot. I had another EL34 design with a higher B+ and 1k 7W screen resistors that I remember being able to touch after an hour of playing with the EL34's at max. Is there something I should check or am I just being a worry wart? Thank you all!!

(Sorry if this is in the wrong place, I didn't see a "Power Amp" section of the forum!)