videos hang

Hi All,

While watching live or recorded TV programs, the video image often freezes, but the sound does not - it continues playing without a hitch.

Could this be lack of memory?

This early 2009 iMac contains

BANK 0/DIMM0:

Size: 1 GB

Type: DDR2 SDRAM

Speed: 800 MHz

Status: OK

Manufacturer: 0xAD00000000000000

Part Number: 0x48594D503131325336344352362D53362020

Serial Number: 0x0000403B

BANK 1/DIMM1:

Size: 4 GB

Type: DDR2 SDRAM

Speed: 800 MHz

Status: OK

Manufacturer: 0x7F7F7F7F7F5D0000

Part Number: 0x436F6D707573746F63782028435358292020

Serial Number: 0x00000000

Could it be caused by an inadequate video card ?

ATI Radeon HD 2600 Pro:

Or perhaps external sources are causing it, like the internet speed (16K), the router, etc...

any ideas, please

GeTe