Errors with 49 Port Block Erupter

[Aefan]

Hi,

I run 49x ASICMINER Block Erupter (335MH/s) in a 49 Port Block Erupter USB hub (Image) with 2x 140mm fans for cooling. The hub is connected to a Raspberry Pi with Minepeon 0.2.4 and cgminer 4.1.0.

When i run the cgminer after a while i get a lot of hardware errors with some miners. i don't know why, but when i restart the miner everything works fine and then after a few minutes a get new errors.
i made 3 screenshots of 3 runs with errors:
first Run
second run
third run

someone any idea why i got this random errors?

greetings

[HellDiverUK]

Try a real computer.  The Pi is a toy with a rubbish USB interface.

[xjack]

If the errors persist after you've gone to a real PC, then your PSU isn't up to snuff.

[philipma1957]

the two gentlemen above have called the most likely 2 problems

 I could tell you lower the sticks to 40 to find out what happens

[Gator-hex]

A TP-Link TL-3020 with OpenWRT is a far superior mining beast than a RPi
http://wiki.openwrt.org/toh/tp-link/tl-mr3020