Here ya go for your errors in your history capture:
As far as your D-channel dropping - maybe no one said anything to you yet, but when carriers add customers to your ring it can cause a D-channel to drop and it is typically after midnight and before 5:00am ... fyi
At least that is what our vendor tells us
TDS0303 l s c (u) Terminal number specified is not designated as a tone detector.
Action:
Severity: Critical. Critical to Monitor: Yes. SNMP trap: Yes
DTC0001 Clock controller tracking on primary source loop.
Action:
Severity: Minor. Critical to Monitor: Yes. SNMP trap: Yes
ERR4291 Music route is undefined.
Action:
Severity: Minor. Critical to Monitor: No. SNMP trap: Yes
ERR0080 tn key Key input from software-unequipped add-on module.
Action: Check SL-1 telephone data. Ensure that add-on module is defined and
that key number is less than last key.
Severity: Minor. Critical to Monitor: Yes. SNMP trap: Yes
ERR0118 Invalid Keymap Download Request for nonexistent add-on module.
Action: Contact your technical support group.
Severity: Minor. Critical to Monitor: No. SNMP trap: Yes