Forced Full Duplex changes to Half Duplex (no mismatch errors)

Guys,
I am going through a very weird situation and wondered if any of you had any ideas on how I could troubleshoot this issue.
I am running a 2960 Cisco, which has a single mode fiber cable which is connected to multiple rstp switches designed by a mining technology company.
The fiber port which connects these switches has "duplex full" written into its configuration. However, after a random amount of time, anywhere from 1 hour to 24 hours, the port is changes to operate in half duplex. This is found by doing a show interfaces status.
At no time whatsoever is there any duplex mismatch errors.
Once i notice that the port is actually operating in half duplex mode, i log into the port, do a "duplex half" then "duplex full".. the port goes back into full duplex for another 1-24 hour period.
Any ideas on why this port keeps jumping into half duplex operation? I really need this port to run in full duplex and cannot understand why the port would go into half duplex operation when the end devices should support full duplex.
Again, i never get any duplex mismatch errors.
I appreciate any troubleshooting tips you can provide.

MSTswitchOVCC#sh version
Cisco IOS Software, C2960S Software (C2960S-UNIVERSALK9-M), Version 12.2(53)SE2, RELEASE SOFTWARE (fc3)
Technical Support: http://www.cisco.com/techsupport
Copyright (c) 1986-2010 by Cisco Systems, Inc.
Compiled Wed 21-Apr-10 06:08 by prod_rel_team
Image text-base: 0x00003000, data-base: 0x01B00000
ROM: Bootstrap program is Alpha board boot loader
BOOTLDR: C2960S Boot Loader (C2960S-HBOOT-M) Version 12.2(53r)SE, RELEASE SOFTWARE (fc3)
MSTswitchOVCC uptime is 1 week, 6 days, 37 minutes
System returned to ROM by power-on
System image file is "flash:/c2960s-universalk9-mz.122-53.SE2/c2960s-universalk9-mz.122-53.SE2.bin"
This product contains cryptographic features and is subject to United
States and local country laws governing import, export, transfer and
use. Delivery of Cisco cryptographic products does not imply
third-party authority to import, export, distribute or use encryption.
Importers, exporters, distributors and users are responsible for
compliance with U.S. and local country laws. By using this product you
agree to comply with applicable laws and regulations. If you are unable
to comply with U.S. and local laws, return this product immediately.
A summary of U.S. laws governing Cisco cryptographic products may be found at:
http://www.cisco.com/wwl/export/crypto/tool/stqrg.html
If you require further assistance please contact us by sending email to
[email protected].
cisco WS-C2960S-24TS-L (PowerPC) processor (revision B0) with 131072K bytes of memory.
Processor board ID FOC1435W6KX
Last reset from power-on
4 Virtual Ethernet interfaces
1 FastEthernet interface
28 Gigabit Ethernet interfaces
The password-recovery mechanism is enabled.
512K bytes of flash-simulated non-volatile configuration memory.
Base ethernet MAC Address       : AC:A0:16:F3:EF:00
Motherboard assembly number     : 73-11910-06
Power supply part number        : 341-0328-01
Motherboard serial number       : FOC14354WTE
Power supply serial number      : LIT142210AX
Model revision number           : B0
Motherboard revision number     : A0
Model number                    : WS-C2960S-24TS-L
Daughterboard assembly number   : 73-11933-04
Daughterboard serial number     : FOC1435437G
System serial number            : FOC1435W6KX
Top Assembly Part Number        : 800-30954-02
Top Assembly Revision Number    : A0
Version ID                      : V02
CLEI Code Number                : COMGG00ARB
Daughterboard revision number   : A0
Hardware Board Revision Number : 0x01
Switch Ports Model              SW Version            SW Image
*    1 28    WS-C2960S-24TS-L   12.2(53)SE2           C2960S-UNIVERSALK9-M
Configuration register is 0xF
MSTswitchOVCC#

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