Fender Deluxe Reverb Reissue - Reverb not working

[Johnny_March]

Hello, I'd love a bit of advice if you can...

I have a newer Fender Deluxe Reverb reissue and the reverb stopped working for a bit. I checked the cables and connections. I'm reading around 200 ohms on the input (white RCA tip-to-sleeve) and very low resistance on the output (red RCA tip-to-sleeve). When I turn the reverb on and off via the footswitch it does nothing.

I then moved on to looking at the tubes and I noticed that when I removed and reseated the reverb recovery tube V4, my reverb came back. My reverb worked for a few weeks and now it went away again. I reseated V4 and my reverb came back again, but I know it won't last forever.

Can anyone recommend anything I should look at to make a permanent fix to this issue? Would this issue be attributed to a bad tube socket or is this more of a component failing in the reverb circuit? Has anyone had a similar experience? I'll include the DRRI schematic for reference.

Thank you!

Fender-65-Deluxe-Reverb-Schematic.pdf

[thetragichero]

clean and retension the offending tube socket