This is a recent problem which I think is due to misbehaving web robots trying to index pages of the system that don't exist, and causing excessive database load.

I've made a change which I think will help (it catches these invalid requests and redirects the robot somewhere more sensible).

I hope that this should have a positive effect on the performance, and thus also get rid of the 503 errors.

If the problem persists please do post on here again about it and I will investigate further.

Thanks

Joe - Voice Admin