Recently a MythTV development team released a bugfix for the version 0.23. There are no many changes in that release but still. The segfault when resolution or aspect ration is changing is fixed. Also the building from the source procedure was improved to allow to do that under different distributions and with various hardware combination.
You can download the MythTV 0.23.1 with plugins and themes here or wait till your distribution maintainers build the binaries fro you.