Timeout on admin login and some tickets

[thepurpleblob]

We recently moved our OTRS system to a new server and all seemed well. However, we are now noticing that attempting to access some tickets results in a long wait and then a browser time-out.

This is also the case when logging in with root@localhost (we cannot). All other usernames and most tickets work properly and quickly.

We have checked the web server logs and have enabled debugging but nothing shows up. Running 'show processlist' in MySQL while waiting shows no activity. I'm not entirely sure what to do next to diagnose this.

Any suggestions are appreciated.