This small SOHO-type switch was subject to an overvoltage on the network cable coming from an ADSL-modem. The modem survived, the switch and one of the attached computers did not. Apologies for the poor image quality, I did not bring my camera gear for this.
In the close-up of the middle part we se that both R22, R24 and C75 are gone.R26 and R28 looks suspicious but may be OK. The Ethernet chips on the reverse side looks fine, and the self test (blinking lights) completed on four of the ports. There is a total of four resistor and capacitor sets, each connected to two ports. As shown in the close-up below, C76, R25 and R27 have also been relieved of their magic blue smoke. As the capacitor is shared between the ports in the set, none of them are working even if only two of the four ports have their resistors blown. It is likely that this is fixable with new resistors and capacitors, as their function is probably to shield the fancy Ethernet control chips from nasty voltages. But, as I do not carry the necessary parts and equipment it was easier to just replace the entire unit for the extortionist price of 30USD at the local brick and mortar store.