Probably need new tubes as noted above.
If that doesn't do the trick, I believe your tweeter is a Seas 25TAF/G which appears to use ferrofluid. Depending on the ease of tweeter partial disassembly, you may be able to change the fluid yourself. Some are simple to do, others not simple at all and your risk damaging the tweeter.
If it was my tweeters, I would not hesitate to send to Millersound who only does speaker repair. He is excellent and if past performance is indicative he will turn them around in a day or two. Price will be very very minimal.
The ferrofluid being bad is definitely a secondary possibility to needing new tubes.