Looking for tube reliability input

[heisthl]

Anyone playing a tube amp professionally should always have an extra set of tubes with them & know how to deal with it. They just go bad. Odd that it showed up in the PI & not a gain stage. I will sure be glad when some of the new 12ax7s wind up bullet proof.

No time to troubleshoot during a show - you just have to swap out the amp. Ditto on bullet proof 12AX7s