Yep - that cannot be the solution for this problem.
The iPronto seems to lost contact with the WLAN
access point and needs some time to "find itself"
or so ?!

After that time the problem vanishs.

Any guy here who has the same problem?

For Philips developer(s) (which read here sometimes):

The solution would be to turn of the display but
not to cut down the connection to the access point!
When I try to ping iPronto the device must be
"online". If the iPronto falls asleep the ping
to iPronto is lost. The device is also turned
off in the access point's member list.

Philips, come on: It cannot be so complicated
to fix a simple WLAN problem like this! There
are other WLAN products in the big Philips company
- ask a colleague to help you fix this (including
WPA encryption).

Best regards,

Kalle