Router LAN/WAN not responding

[Sunny]

Hi,

I have a RT-AC68U and with an ADSL connection 5/1 Mpbs .

Last night I decided to upload 5GB of photos/videos to Google Drive and whilst uploading my whole network stopped responding.... WiFi drop outs, LAN devices cant communicate with each other, cant reach websites. As soon as I pause the upload everything works normal again... I don't haven't QOS enabled and ran top command to find the following, any ideas? :

Mem: 74400K used, 181292K free, 0K shrd, 2776K buff, 9716K cached
CPU: 0.0% usr 4.5% sys 0.0% nic 95.4% idle 0.0% io 0.0% irq 0.0% sirq
Load average: 0.01 0.05 0.05 1/98 8776
PID PPID USER STAT VSZ %VSZ CPU %CPU COMMAND
8776 8773 admin R 1388 0.5 0 4.5 top
454 1 admin S 6620 2.5 0 0.0 httpd -i br0
453 1 admin S 6352 2.4 1 0.0 httpds -s -p 8443 -i br0
459 1 admin S 6228 2.4 0 0.0 watchdog
1 0 admin S 6196 2.4 0 0.0 /sbin/preinit
1097 1 admin S 6180 2.4 1 0.0 bwdpi_wred_alive
977 1 admin S 6180 2.4 1 0.0 ntp
1030 1 admin S 6180 2.4 0 0.0 disk_monitor
757 1 admin S 6180 2.4 0 0.0 usbled
432 1 admin S 6180 2.4 1 0.0 /sbin/wanduck
511 1 admin S 6180 2.4 0 0.0 bwdpi_check
512 1 admin S 6180 2.4 0 0.0 hour_monitor
439 1 admin S 6180 2.4 1 0.0 wpsaide
463 459 admin S 6180 2.4 1 0.0 ots
353 1 admin S 6172 2.4 1 0.0 console
945 1 admin S 5556 2.1 1 0.0 /usr/sbin/smbd -D -s /etc/smb.conf
944 1 admin S 5352 2.0 0 0.0 nmbd -D -s /etc/smb.conf
1073 1069 admin S 3732 1.4 1 0.0 data_colld -i 1800 -p 43200 -b -w
1068 1 admin S 3732 1.4 0 0.0 data_colld -i 1800 -p 43200 -b -w
1099 1069 admin S 3732 1.4 0 0.0 data_colld -i 1800 -p 43200 -b -w