[zaphod24]

Thanks for the suggestions. Any suggestions for values to start with and if overvolting is needed?

Modest overclock:

Code:

sdram_freq=500
v3d_freq=400

High overclock:

Code:

sdram_freq=550
core_freq=500
v3d_freq=500
over_voltage=4
sdram_schmoo=0x02000020

You could try going to sdram_freq=600 too but that bay introduce instability.

With any overclock if you start seeing instability then lower the overclock level. In my experience:
The modest setting will work on almost all Pi's.
The high setting will work on the majority of Pi's.
sdram_freq=600 will be reliable on less than half the Pi's.

Ok, I tried:

gpu_mem=320
sdram_freq=550
core_freq=500
v3d_freq=500
over_voltage=4
sdram_schmoo=0x02000020

Unfortunately it still causes the "invalid format" when bringing up an OSD like info. I can try to cut a clip down to a few seconds and upload it somewhere.