Upright piano a key don't hit the string most of a time when a dampening pedal is on. How fix it DIY

[maxim_tuner]

https://youtu.be/dRs_98FBrmY

• In the provided video has excessive high 'the let-off' of the upright piano results in weak hammer strikes on the strings when the soft pedal/dampening pedal is engaged there. To address this issue through a do-it-yourself (DIY) approach, follow the steps below:
  
  Problem Observation:
  The key exhibit insufficient hammer strike force on the strings, especially noticeable when the soft pedal is activated.
  
  Potential Causes:
  1. 'The Capstan Screw' Adjustment:
  - Attempt to raise 'the capstan screw' by lightly unscrewing it from the key.
  - If no satisfactory changes occur through this adjustment, consider the following potential cause.
  
  2. 'The Let-off Regulation':
  - Examine the positioning of 'the jack' relative to 'the let-off' for key.
  - It appears that the bottom of 'the jack' may be incorrectly located concerning 'the let-off'.
  
  3. Condition Felt of 'The Let-off' :
  - Investigate the condition of the felt associated with key.
  - It is possible that the felt has shrunk, hardened, or become completely loose.
  4. *Condition 'the spring of the jack of the wippen'
  - Investigate the condition of 'the spring'. If it weak need pull it up slightly to increase its elasticity. And return it under 'the jack of the wippen'
  
  DIY Fix:
  1. Capstan Screw Adjustment:
  - Attempt to raise 'the capstan screw' by lightly unscrewing it from the key.
  - If the issue persists, proceed to the next step.
  
  2. 'The Let-off' Regulation Adjustment:
  - Carefully try lower down 'the let-off' for keys the thin stick.
  - Insert the stick into 'the let-off' regulation screw' and turn it clockwise.
  
  By addressing these potential causes and making the suggested adjustments, it is anticipated that the hammer strikes on the strings for key will be more consistent and effective when the dampening pedal is engaged even.