Is it just me or is my Mesa Dual Rec get noisy after its been on over an hour?

[videodrone]

I started to notice this the other day, tonite Im doing more recording so ill pay more attention tonite,

But it seems like I dont have a noise problem with my amp until after its been on a lil more than an hour and a half, than I get this white noise sound form the amp,

Is that common with failng tubes or my amp model?

 

[MemoGtr]

thats not normal
i think there's something wrong with the amp

 

[Light]

Get the tubes checked.


Light

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