I had a similar problem with a Fender Twin Reverb Amp.
The original spring can has been replaced with a similar new one (code is the same) because of a broken spring.
Solution:
Place the springs up side down.
Add some shock absorbing material under the springcan.
Fix the springcan with velcro to the bottom of the cabinet.
Use bigger rubber feet under the cabinet.
This at least worked with this particular amp.
Good luck.
The original spring can has been replaced with a similar new one (code is the same) because of a broken spring.
Solution:
Place the springs up side down.
Add some shock absorbing material under the springcan.
Fix the springcan with velcro to the bottom of the cabinet.
Use bigger rubber feet under the cabinet.
This at least worked with this particular amp.
Good luck.