You may have a tube problem. Probably the best thing to do is to test them on a tube tester to be sure. Then again, it's nice to have a spare set of tubes, so you might just buy them and replace them one at a time to see if you can isolate a defective tube. Might swap them all at once just to see if its a tube or not. If so, then start putting the old ones back in until the radio no longer works. You may have more than one bad tube, so try 'em all that way.

But don't be surprised if it isn't a tube at all. If you buy them all, do so without expectation. You will have a spare set of tubes at the least. You may find that the capacitors have gone bad or that you have a defective field coil in your speaker. If the tubes aren't what is causing your problem, I'd check the capacitors. If they are original, then they're almost certainly bad.

Wayne