Ok, update on everything done...
Sophos and Rapport uninstalled...downloaded and reinstalled Sierra, backed up via time machine.
Only had one safari extension (add block plus), it was up to date but uninstalled it.
Restarted, restarted in safe-mode, restarted again.
Once all loaded checked CPU with just system running...there was an initial spike, sat and watched while it settled, watched for a few minutes, CPU stayed at over 97% idle...top processes were 'kernel_task, Go for Gmail. WindowServer, Activity Monitor'.
Launched Safari and sat with my FB page open, again, initial spike but once settled CPU stayed above 97% idle, same processes active as above.
Went to FB news feed in safari, initial spike but again after settling CPU stayed at over 97% idle, same active processes as above with the addition of the Facebook url.
After all this i ran EtreCheck again...
EtreCheck version: 3.0.5 (309)
Report generated 2016-09-24 19:56:07
Download EtreCheck from https://etrecheck.com
Runtime 1:54
Performance: Excellent
Click the [Support] links for help with non-Apple products.
Click the [Details] links for more information about that line.
Problem: Other problem
Hardware Information: ⓘ
MacBook Air (11-inch, Mid 2011)
[Technical Specifications] - [User Guide] - [Warranty & Service]
MacBook Air - model: MacBookAir4,1
1 1.8 GHz Intel Core i7 CPU: 2-core
4 GB RAM Not upgradeable
BANK 0/DIMM0
2 GB DDR3 1333 MHz ok
BANK 1/DIMM0
2 GB DDR3 1333 MHz ok
Bluetooth: Old - Handoff/Airdrop2 not supported
Wireless: en0: 802.11 a/b/g/n
Battery: Health = Normal - Cycle count = 950
Video Information: ⓘ
Intel HD Graphics 3000
Color LCD 1366 x 768
System Software: ⓘ
macOS Sierra 10.12 (16A323) - Time since boot: less than an hour
Disk Information: ⓘ
APPLE SSD SM128C disk0 : (121.33 GB) (Solid State - TRIM: Yes)
EFI (disk0s1) <not mounted> : 210 MB
Recovery HD (disk0s3) <not mounted> [Recovery]: 650 MB
Macintosh HD (disk1) / : 120.10 GB (45.26 GB free)
Encrypted AES-XTS Unlocked
Core Storage: disk0s2 120.47 GB Online
USB Information: ⓘ
Apple Inc. Apple Internal Keyboard / Trackpad
Apple Inc. BRCM20702 Hub
Apple Inc. Bluetooth USB Host Controller
Thunderbolt Information: ⓘ
Apple Inc. thunderbolt_bus
Configuration files: ⓘ
/etc/sudoers, File size 2299 but expected 1563
Gatekeeper: ⓘ
Mac App Store and identified developers
System Launch Agents: ⓘ
[not loaded] 8 Apple tasks
[loaded] 174 Apple tasks
[running] 72 Apple tasks
[killed] 17 Apple tasks
17 processes killed due to insufficient RAM
System Launch Daemons: ⓘ
[not loaded] com.apple.jetsamproperties.Mac.plist (2016-08-26) [Support]
[not loaded] 37 Apple tasks
[loaded] 170 Apple tasks
[running] 82 Apple tasks
[killed] 15 Apple tasks
15 processes killed due to insufficient RAM
Launch Daemons: ⓘ
[loaded] com.apple.installer.osmessagetracing.plist (2016-09-13)
User Launch Agents: ⓘ
[loaded] com.apple.AddressBook.ScheduledSync.PHXCardDAVSource.F00661D4-E7EA-4A05-9787-5D5 800F45AD3.plist (2011-10-13)
User Login Items: ⓘ
iTunesHelper Application (/Applications/iTunes.app/Contents/MacOS/iTunesHelper.app)
SpeechSynthesisServer Application Hidden (/System/Library/Frameworks/ApplicationServices.framework/Versions/A/Frameworks /SpeechSynthesis.framework/Versions/A/SpeechSynthesisServer.app)
Internet Plug-ins: ⓘ
QuickTime Plugin: 7.7.3 (2016-09-14)
Silverlight: 5.1.30514.0 - SDK 10.6 (2014-08-12) [Support]
3rd Party Preference Panes: ⓘ
None
Time Machine: ⓘ
Skip System Files: NO
Mobile backups: ON
Auto backup: YES
Volumes being backed up:
Macintosh HD: Disk size: 120.10 GB Disk used: 74.85 GB
Destinations:
MacBook [Network]
Total size: 749.66 GB
Total number of backups: 6
Oldest backup: 16/09/2016, 05:46
Last backup: 24/09/2016, 19:22
Size of backup disk: Excellent
Backup size 749.66 GB > (Disk size 120.10 GB X 3)
Top Processes by CPU: ⓘ
7% WindowServer
3% mds
2% fontd
1% kernel_task
1% com.apple.AmbientDisplayAgent
Top Processes by Memory: ⓘ
448 MB kernel_task
299 MB mdworker(17)
139 MB Go for Gmail
102 MB assistant_service
61 MB UserEventAgent(2)
Virtual Memory Information: ⓘ
148 MB Free RAM
3.85 GB Used RAM (642 MB Cached)
183 MB Swap Used
Diagnostics Information: ⓘ
Sep 24, 2016, 07:36:46 PM Self test - passed
Sep 24, 2016, 05:49:23 PM /Library/Logs/DiagnosticReports/backupd_2016-09-24-174923_[redacted].cpu_resour ce.diag [Details]
/System/Library/CoreServices/backupd.bundle/Contents/Resources/backupd
Sep 23, 2016, 10:47:09 PM ~/Library/Logs/DiagnosticReports/iTunes_2016-09-23-224709_[redacted].crash
com.apple.iTunes - /Applications/iTunes.app/Contents/MacOS/iTunes
Sep 23, 2016, 07:01:21 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-190121_ [redacted].crash
/System/Library/Frameworks/WebKit.framework/Versions/A/XPCServices/com.apple.We bKit.WebContent.xpc/Contents/MacOS/com.apple.WebKit.WebContent
Sep 23, 2016, 06:36:41 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-183641_ [redacted].crash
Sep 23, 2016, 06:27:47 PM ~/Library/Logs/DiagnosticReports/cloudphotosd_2016-09-23-182747_[redacted].cras h
com.apple.cloudphotosd - /System/Library/CoreServices/cloudphotosd.app/Contents/MacOS/cloudphotosd
Sep 23, 2016, 05:46:26 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-174626_ [redacted].crash
Sep 23, 2016, 05:38:00 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-173800_ [redacted].crash
Sep 23, 2016, 05:34:32 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-173432_ [redacted].crash
Sep 23, 2016, 05:21:35 PM ~/Library/Logs/DiagnosticReports/rapportd_2016-09-23-172135_[redacted].crash
/Library/Rapport/*/rapportd.app/Contents/MacOS/rapportd
Sep 23, 2016, 05:03:13 PM ~/Library/Logs/DiagnosticReports/rapportd_2016-09-23-170313_[redacted].crash
Sep 23, 2016, 05:01:25 PM ~/Library/Logs/DiagnosticReports/rapportd_2016-09-23-170125_[redacted].crash
Sep 23, 2016, 04:35:26 PM ~/Library/Logs/DiagnosticReports/rapportd_2016-09-23-163526_[redacted].crash
Sep 23, 2016, 04:09:13 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-160913_ [redacted].crash
Sep 23, 2016, 03:57:43 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-155743_ [redacted].crash
Sep 23, 2016, 03:48:13 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-154813_ [redacted].crash
Sep 23, 2016, 03:35:49 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-153549_ [redacted].crash
Sep 23, 2016, 03:34:25 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-153425_ [redacted].crash
Sep 23, 2016, 03:12:23 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-151223_ [redacted].crash
Sep 23, 2016, 03:10:18 PM ~/Library/Logs/DiagnosticReports/com.apple.WebKit.WebContent_2016-09-23-151018_ [redacted].crash
Sep 21, 2016, 08:51:43 PM ~/Library/Logs/DiagnosticReports/Safari_2016-09-21-205143_[redacted].crash
com.apple.Safari - /Applications/Safari.app/Contents/MacOS/Safari