I'm sure you have fixed this by now... But solution is...
Check the hammer phasing. Adjust hammer phasing if
6. On the control panel, press the = + > keys to unlock the ENTER key.
“ENTER SWITCH UNLOCKED” briefly displays. (If “LOCKED” displays,
simply press = and > again. This is the default key combination. The lock/
unlock key combination can be programmed by the user. If = + > does
not unlock ENTER, get the combination from the user.)
7. Press the ; key. “OFFLINE / DIAGNOSTICS” displays.
8. Press >. “DIAGNOSTICS / Printer Tests” displays.
9. Press >. “Printer Tests / Shift Recycle” displays.
10. Press ; until “Printer Tests / Phase Printer” displays.
11. Press ENTER. The display shows “Printer Tests / Phase Printer” and the
test begins. The current phasing value is printed on the left of the printed
pattern of all H’s. As the pattern prints, compare the H’s to the figure
below. If the phasing needs adjustment, go to step 12. If the phasing is
OK, go to step 15.
12. Press >: The current phase index displays. Press > again: An asterisk (*)
appears next to the phase value.
13. Press < to increase or ; to decrease the phasing index value, then press
ENTER to activate the value as it prints. Continue to increase or decrease
the phasing index until the pattern of H’s is acceptable.
14. Press = twice: “Printer Tests / Phase Printer” displays.
15. Press ENTER to stop the test.
16. Press CLEAR. “OFFLINE / CONFIG. CONTROL” displays.
17. Press = + > (or the key combination set by the user). “ENTER SWITCH
LOCKED” briefly displays.
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